Journal articles: 'Aluminium Alloys - Semisolid Die Casting'

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Motegi, Tetsuichi, Fumi Tanabe, and Eiji Sugiura. "Continuous Casting of Semisolid Aluminium Alloys." Materials Science Forum 396-402 (July 2002): 203–8. http://dx.doi.org/10.4028/www.scientific.net/msf.396-402.203.

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Jarfors, Anders E. W. "A Comparison Between Semisolid Casting Methods for Aluminium Alloys." Metals 10, no. 10 (October 13, 2020): 1368. http://dx.doi.org/10.3390/met10101368.

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Semisolid casting of aluminium alloys is growing. For magnesium alloys, Thixomoulding became the dominant process around the world. For aluminium processing, the situation is different as semisolid processing of aluminium is more technically challenging than for magnesium. Today three processes are leading the process implementation, The Gas-Induced Superheated-Slurry (GISS) method, the RheoMetal process and the Swirling Enthalpy Equilibration Device (SEED) process. These processes have all strengths and weaknesses and will fit a particular range of applications. The current paper aims at looking at the strengths and weaknesses of the processes to identify product types and niche applications for each process based on current applications and development directions taken for these processes.

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D’Errico, Fabrizio, Daniele Casari, Mattia Alemani, Guido Perricone, and Mauro Tosto. "INDUSTRIAL SEMISOLID CASTING PROCESS FOR SECONDARY ALUMINIUM ALLOYS FOR DECARBONISING LIGHTWEIGHT PARTS IN AUTOMOTIVE SECTOR." MATEC Web of Conferences 326 (2020): 06007. http://dx.doi.org/10.1051/matecconf/202032606007.

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The life cycle holistic approach for the automotive sector highlighted how much important is working on decarbonisation of Al casting processes to produce vehicle components. Broadening the use of recycled aluminium alloys, instead of high energy intensive primary aluminium alloys, is key for environment preservation. While primary aluminium alloys are preferred by automotive original equipment manufacturers (OEMs) because impurities (mainly Fe) present in secondary aluminium alloys might cause fatigue properties decay, a new semisolid state process route has been developed at Brembo to drastically reduce the sensitivity of cast aluminium to Fe impurities. Based on these premises, during the CRAL European project in the framework of the LIFE Programme, an industrial prototype machinery - a vertical high pressure die casting machine - has been designed and constructed to inject secondary aluminium in the semisolid state. A number of A357 Fe-enriched brake callipers manufactured via the new process route have been fully investigated by fatigue tests, SEM and OM analyses in order to validate the new eco-sustainable product compared to conventional ones manufactured with primary aluminium by gravity casting.

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Qi, Ming Fan, Yong Lin Kang, Yuan Hao Zheng, Ji Cheng Wang, Gu Nan Li, and Ying Zhang. "Industrialization of Aluminum Alloy Uniform Solidification Controlled Rheological Die Casting." Solid State Phenomena 327 (January 10, 2022): 163–71. http://dx.doi.org/10.4028/www.scientific.net/ssp.327.163.

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An efficient and low-cost aluminum alloy uniform solidification control technology, namely, air-cooled stirring rod (ACSR) process, has been developed for preparing large volume semisolid slurry. The semisolid slurry preparation process is connected with the die-casting machine to form multiple integrated intelligent rheological die-casting production lines for the efficient preparation of rheological die-casting of large-scale thin-walled aluminum alloys. At present, the ACSR process can produce 40 kg of large-volume semisolid slurry with a solid phase ratio of 25% to 35% within 30 s. This rheological die-casting process has been industrialized for the preparation of high-quality aluminum alloy large-scale thin-walled parts, such as new energy vehicles and 5G communications. Typical products produced by this process include heat dissipation housings for 5G communications, filter housings, antenna chassis and three-electric structural shell, end cover, and ABS system valve body for new energy vehicles. Compared with traditional die castings, aluminum alloy castings prepared by the new process not only have fine and spherical microstructures, good surface quality, and fewer internal pores but also enjoys more excellent mechanical properties and thermal conductivity.

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Proni, Cecilia Tereza Weishaupt, Leandro Cássio de Paula, Luis Vanderlei Torres, and Eugênio José Zoqui. "Evaluation of Al-5wt%Si-5wt%Zn as Raw Material for Semisolid Forming." Solid State Phenomena 285 (January 2019): 339–44. http://dx.doi.org/10.4028/www.scientific.net/ssp.285.339.

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Designing new alloys for semisolid processing is key to the success of semisolid materials technology. While aluminium-silicon and aluminium-zinc alloys have been tested as potential raw materials, ternary aluminium alloys containing silicon and zinc have yet to be tested. As such alloys may exhibit the rheological behaviour required for semisolid forming and the excellent final mechanical properties of Al-Zn alloys, we investigated the thermodynamic aspects of the solid-liquid transition of Al-5.5wt%Si-5wt%Zn alloy, the morphological stability of this alloy in the semisolid temperature range and the corresponding rheological behaviour. Thermo-Calc® simulation software was used to evaluate the solid-to-liquid transition and identify the semisolid temperature range within which the liquid-fraction sensitivity is low and the process is therefore controllable. Based on the results of the simulation, a target temperature of 588 °C was chosen. This is sufficient to produce a liquid fraction of 55 % and a corresponding liquid-fraction sensitivity (dfl/dT) of 0.009 C-1. The Al-5wt%Si-5wt%Zn alloy was prepared by conventional casting in a refrigerated copper mould without grain refining, and the alloy was characterized to determine the stability of the microstructure after heating to 588 °C and holding at this temperature for holding times of 0, 30, 60, 90 and 120 s. The same temperature and holding times were used to evaluate the rheological behaviour in hot compression tests. A grain size of 170 μm, globule size of 100 μm and circularity of 0.6 were achieved, leading to a maximum apparent viscosity of 2 x 105 Pa.s, which rapidly decreased to 3 x 104 Pa.s after a shear rate of 9 s-1 was reached.

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Möller, Heinrich, Gonasagren Govender, Pierre Rossouw, and Waldo Stumpf. "The Influence of Prior Natural Aging on the Subsequent Artificial Aging Response of Aluminium Alloy A356 with Respective Globular and Dendritic Microstructures." Advances in Materials Science and Engineering 2011 (2011): 1–6. http://dx.doi.org/10.1155/2011/375150.

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Alloy A356 is one of the most popular alloys used for semisolid metal forming. The heat treatment cycles that are currently applied to semisolid processed components are mostly those that are in use for dendritic casting alloys. The assumption has been made that these heat treatments are not necessarily the optimum treatments, as the difference in solidification history and microstructure of SSM processed components should be considered. The objective of this study is to determine whether dendritic A356 behaves in a similar way to globular A356 in terms of its response to artificial aging with or without prior natural aging. The results indicate that the differences in microstructures (globular or dendritic) do not have a noteworthy effect on the heat treatment response. It is also shown that strong linear correlations are found between T4 and T6 hardness and wt% Mg of A356, regardless of the casting technique used.

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Azpilgain, Zigor, Inaki Hurtado, R. Ortubay, I. Landa, and J. Atxa. "Semisolid Forging of 7000 Series Aluminum Alloys." Solid State Phenomena 116-117 (October 2006): 758–61. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.758.

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The achievement of lighter automotive components is an important driving force in the development and optimization of casting techniques. In this sense, semisolid forming is an emerging technology that has allowed the production of security components using aluminum alloys. The foundry alloys A356 and A357 remain, up to the present, the most used alloys for the semisolid processing of components. Nevertheless, several authors have pointed out the gain in properties that other alloy families could provide. In the present work, thixoformability of 7000 series aluminum alloys is studied. Thermodynamic calculations (CALPHAD method) and calorimetric experiments have been performed to determine the composition of alloys with an optimum process window. A modification of the 7075 alloy is proposed in order to improve its thixoformability parameters and optimize the process control. A simple component has been produced by semisolid forging and mechanical properties have been measured from tensile samples.

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Fracchia, Elisa, Ivano Gattelli, and Marco Actis Grande. "Characterisation of Residual Stresses of Rheocast Al Alloy." Solid State Phenomena 347 (August 24, 2023): 31–37. http://dx.doi.org/10.4028/p-cq6pqs.

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Rheocasting is a semisolid casting process allowing to obtain near-net shape parts. Through the Rheocasting process, it is possible to achieve aluminium castings having a low grade of porosity if compared to traditional die-casting methods, encouraging the production of automotive frame parts. However, casting processes, as commonly known, may cause tensile residual stresses inside the parts. On the other hand, compressive stresses inside castings can significantly increase the life of components: residual compressive stresses increase the material's resistance by counteracting crack initiation and propagation. The cracks propagate when the material is under tensile stress, while the Rheocasting technique seems to promote compressive stresses inside the castings. This work aims to analyse an aluminium rheocasted frame component for race cars in both the as-cast and heat-treated conditions. First, the mechanical properties of the components were evaluated in terms of tensile tests and microhardness. Then, residual stresses were measured at specific points of the casting. Finally, the evolution of the residual stresses inside the component before and after heat treatment led to assessing the effect of the Rheocasting process condition and the heat treatment, proving the marked advantage of using such a technology.

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Kapranos, Plato, Ryoji Nakamura, Ermanno Bertoli, Annalisa Pola, Zigor Azpilgain, and Inaki Hurtado. "Thixo-Extrusion of 5182 Aluminium Alloy." Solid State Phenomena 141-143 (July 2008): 115–20. http://dx.doi.org/10.4028/www.scientific.net/ssp.141-143.115.

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Extrusion is a well established technology for the production of complex sections of aluminium alloys. Thixo-extrusion in comparison to traditional hot-extrusion offers several advantages such as lower extrusion and friction forces, higher material fluidity, longer tool life etc. Aluminium alloy 5182 is an important commercial alloy characterized by high strength and ductility, high corrosion resistance and good formability; it is commonly used for the production of wrought automotive components and it is also suitable for semi-solid applications thanks to its wide solidification range. The aim of this paper is to attempt the shaping of 5182 Al-Mg alloy through the thixo-extrusion process using a ceramic tool and evaluating the effect of different routes of making the feedstock on the semisolid microstructure. Particularly, two different methods were investigated: Near-solidus casting and Roll-casting using a cooling slope. All the samples produced were characterized by metallographic analysis in order to measure globule size and shape factor, as the main criteria used for assessing thixo-formability.

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Santos, Jorge, Anders E. W. Jarfors, and Arne K. Dahle. "Filling, Feeding and Defect Formation of Thick-Walled AlSi7Mg0.3 Semi-Solid Castings." Solid State Phenomena 256 (September 2016): 222–27. http://dx.doi.org/10.4028/www.scientific.net/ssp.256.222.

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Aluminium semi-solid castings have gained increased attention due to their superior mechanical properties, lower porosity compared to conventional high pressure die cast material. These characteristics suggests that semi-solid casting should be suitable to produce thick-walled structural components, yet most successful applications of semisolid casting have been for thin-walled components. There is a lack of understanding on filling and feeding related defect formation for semi-solid castings with thick-walled cross-sections. In the current study an AlSi7Mg0.3 aluminium alloy was used to produce semi-solid castings with a wall thickness of 10mm using a Vertical High Pressure Die Casting machine. The RheoMetalTM process was used for slurry preparation. The primary solid α-Al fraction in the slurry was varied together with die temperature. The evaluation of the filling related events was made through interrupted shots, stopping the plunger at different positions. Microscopy of full castings and interrupted test samples were performed identifying the presence of surface segregation layer, shear bands, gas entrapment, shrinkage porosity as well as burst feeding.

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Bünck, Matthias, Fabian Küthe, Andreas Bührig-Polaczek, Alexander Arnold, Bernd Friedrich, and Roger Sauermann. "Semi-Solid Casting of High-Reactive Wrought Alloys by Means of the Alloy AlLi2.1Mg5.5ScZr (AA1420*)." Solid State Phenomena 141-143 (July 2008): 145–50. http://dx.doi.org/10.4028/www.scientific.net/ssp.141-143.145.

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Semi-solid forming offers new potentials for processing of high reactive and hot crack susceptible aluminium-lithium wrought alloys. With the tailored alloy AA1420* (AlLi2.1Mg5.5 +Sc+Zr) a promising material for thixoforming with achievable high strength of up to 500MPa tensile strength and over 400MPa yield strength concomitant with its low density of 2,46g/cm3 is achievable. Due to high solid fractions the effect of solidification shrinkage could be sufficiently decreased with the result of hot-tear-free casting. Simulation supported a critical to cast automotive tie rod was exemplarily manufactured via semisolid- technology with promising results. Furthermore with an improved and advanced heat treatment enhanced mechanical properties, comparable to those of rolled AA1420, were achieved.

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Saklakoğlu, Nurşen, Yücel Birol, and Şefika Kasman. "Microstructural Evolution of ETIAL 160 Aluminium Alloy Feedstock Produced by Cooling Slope Casting." Solid State Phenomena 141-143 (July 2008): 575–80. http://dx.doi.org/10.4028/www.scientific.net/ssp.141-143.575.

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Owing to its superior flow and mould-filling capability, a fully globular structure is essential for semisolid processing technologies. The present work was undertaken to identify the cooling slope casting process parameters that, upon heating to the semisolid state, gives the required globular structure for the ETIAL 160 alloy. Of the two pouring temperatures investigated, 605 °C and 615 °C, the lower pouring temperature was found to provide more globular grains surrounded by liquid phases.

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Pola, Annalisa, Alberto Arrighini, and Roberto Roberti. "Effect of Ultrasounds Treatment on Alloys for Semisolid Application." Solid State Phenomena 141-143 (July 2008): 481–86. http://dx.doi.org/10.4028/www.scientific.net/ssp.141-143.481.

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Semisolid metallic alloys are commercially produced by means of mechanical or electromagnetic stirring. Among the mechanical devices, the rotating pin immersed in a solidifying alloy seems to be easier to manage in industrial practice although it can induce some porosity, depending on the shape of the pin. As known, ultrasounds are mechanical waves which, when applied to liquid metals, increase the number of solidification nuclei, so that the cast products show superior mechanical performances, as a consequence of the finer grain structure. In this paper the use of ultrasound waves applied to different alloys during solidification was studied in order to obtain feedstock for semisolid die-casting application. A dedicated ultrasound power unit, together with a proper sonicator pin, was designed and manufactured by the authors and, subsequently, the effect of the ultrasonic treatment on the microstructure of A356 aluminum alloy and ZA27 zinc alloy was investigated. All the produced samples were characterized by metallographic analyses to measure the globule size and shape factor, which are main criteria for thixo-microstructure assessment. The results were compared to those obtained with traditional mechanical stirring, showing the higher capability of ultrasound treatment in producing better semisolid microstructure. An optimized combination of process parameters seems to be necessary to get a reasonable thixotropic structure in treating ZA27 alloy. Less severe production conditions are needed in the case of aluminum alloy, revealing the potentiality of ultrasounds as an alternative treatment to traditional mechanical stirring, with the further advantage of alloy degassing and grain refinement, without the use of expensive addictions (TiB2). Trials were finally performed on a continuous casting pilot plant in combination with electromagnetic stirring to produce semisolid billets.

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Côté, Pascal, Bryksi Vlastimil, and Barbora Bryksí Stunová. "Case Study: Engine Bracket Made by Rheocasting Using the SEED Process." Solid State Phenomena 285 (January 2019): 441–45. http://dx.doi.org/10.4028/www.scientific.net/ssp.285.441.

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In the context of increasing needs for lightweighting vehicles, semisolid casting of aluminium components is a proven route that can be efficiently applied for automotive parts. Although semisolid forming has not yet reached the market penetration that suits its actual potential, it is currently and efficiently used in many applications around the world on a daily basis. An example of such will be shown. This paper presents a case study on the application of the SEED rheocasting technology for the casting of an engine bracket. The part is made of the widely used AlSi7Mg0.3 alloy and is heat treated in T6 condition to benefit from the enhanced mechanical properties made possible by semi-solid forming. Throughout the development phase, different aspects associated with semisolid casting, such as slurry condition, gate design, mold filling behaviour, lubrication, blistering and others, were addressed successfully. In the final, the combination of the SEED technology with a thorough development process and the specific casting rules for semi-solid forming led to actual commercial production and contributed to weightsaving on the actual part as compared to a former design made from high pressure die casting.

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Kaskani, Mehdi, and Behzad Niroumand. "On Non-Dendritic Microstructure Formation during Sand Casting of A356 Alloy." Solid State Phenomena 192-193 (October 2012): 433–40. http://dx.doi.org/10.4028/www.scientific.net/ssp.192-193.433.

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The purpose of this study was to develop a new method for formation of non-dendritic microstructure during sand casting of aluminum alloys without any previous special processing. For this purpose, sand molds with three different types of running systems were designed. The first design included a traditional reverse tapered vertical sprue. The second design was similar to the first one except for a conical sand core placed inside the lower half portion of the sprue creating a narrow gap for the flow of the melt into the mold. In the third design, the core was fitted with metal chills. Molten A356 alloy was then cast from fully liquid state under gravity and centrifugal casting conditions in the molds and the microstructures of the castings were studied. The results showed that non-dendritic microstructure could be achieved by using the last design under low superheat temperature and centrifugal casting conditions. The findings can pave the way for small quantity production of semisolid castings in expendable molds.

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Niklas, Fabian. "New Addressable Applications for Rheocasting to Escape from an Oversupplied Market." Solid State Phenomena 348 (August 28, 2023): 61–67. http://dx.doi.org/10.4028/p-k3dfyn.

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The current market change of aluminium HPDC castings started with the “Dieselgate”. First, there was a shift from diesel to petrol engines. In the second step, hybrid and battery-powered cars gained significant market shares in sales statistics. Therefore, lucrative powertrain components are falling away. As powertrain foundries still want to utilize their machines to capacity, they are pushing into the structural castings market. As a result, there is an oversupply of casting machines here, which massively depresses prices and, thus, margins for tenders. With rising energy costs, these declining margins were eaten up, bringing foundries into crisis. Implementing Rheocasting at the existing die-casting cells is the solution to move into new market shares that are now not accessible in conventional HPDC.One of the new applications is electronic housings, high wall thickness parts, and fatigue bearing parts. These parts are commonly manufactured in sand or gravity castings because of their high wall thickness and low tolerance of porosity. Rheocasting is the perfect process for high-wall thickness components. Because of the semisolid melt preparation and the lamellar filling behavior, these components can be manufactured from the same alloy without pores or voids.This flow behavior of the semisolid slurry also results in a longer flow length. Slower casting speeds and lower pressure settings result in lower clamping forces. This gives an advantage in production costs and targets battery constructions made of castings and sheet metal. Structural battery housings must be leak-tight, even in a crash event. Having it in one casting instead of an assembly reduces the leakage area and improves crash performance.Another industry that relies on Rheocasting is the telecommunications industry. The power electronics in these 5G modules are significantly larger and generate much more waste heat. Until now, many antennas have been actively cooled or milled from a block of aluminum. The milled housings are significantly too expensive to enable series production. Therefore, the goal is to reproduce the passively cooled modules in die casting. Due to the process, the thermal conductivity in conventional HPDC is around 120 to 130 W/m*K. Similarly, no slim cooling fins can be formed. Only the Rheocasting process makes it possible to cast other alloys with low proportions of alloying elements, such as AlSi2Mn. This allows fins with a wall thickness of down to 0.4 mm and thermal conductivity of up to 190 W/m*K.Rheocasting enables access to market segments out of reach. These bring an unbeatable cost advantage against the current suppliers: gravity and sand casters. The low cycle time in Rheocasting brings back the high margins needed to sustain the business. Also, these products can be delivered with even better properties on smaller casting machines.

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Yang, M. B., H. J. Hu, B. Dai, and L. W. Tang. "Compression behaviour of semisolid YL112 die casting aluminium alloy following isothermal heat treatment." International Journal of Cast Metals Research 20, no. 4 (August 2007): 198–201. http://dx.doi.org/10.1179/136404607x249770.

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Torres, Luis Vanderlei, Cecilia Tereza Weishaupt Proni, and Eugênio José Zoqui. "Rheological Behavior in the Semisolid State of Al-Si-Cu Alloys Produced by ECAP." Solid State Phenomena 347 (August 24, 2023): 135–40. http://dx.doi.org/10.4028/p-zz3xy6.

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It is fundamental in thixoforming to have a refined microstructure that, when heated to the semisolid state, consists of a mixture of small spheres immersed in liquid as this ensures the best rheological properties. The present work therefore aims to analyze the rheological behaviour of aluminum-silicon-copper alloys, namely, Al5Si2.8Cu, Al6Si2.8Cu and Al7Si2.8Cu. The alloys were produced by conventional casting and then deformed by ECAP in one pass in a die containing two channels of the same cross-sectional area forming an angle of 120°. After being processed by ECAP, the alloys were heated to semisolid temperatures, i.e., temperatures corresponding to a solid fraction of 45 %, and kept in the semisolid state for 0, 30 and 90 s, after which they were subjected to hot compression tests. The structures of the three alloys had an excellent response to recovery and recrystallization mechanisms, with refined microstructures that led to the formation of very fine spheres immersed in liquid in the semisolid state. The best rheological behaviour was obtained for the Al5Si2.8Cu alloy, which had an apparent viscosity of the order of 103 Pa.s. The findings suggest that this simple ECAP process is a promising route for the production of semisolid feedstock for use in thixoforming.

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Haga, Toshio, Kazuki Yamazaki, and Shinichi Nishida. "High Speed Roll Casting of Al-5%Mg Strip at Semisolid Condition." Solid State Phenomena 348 (August 28, 2023): 7–14. http://dx.doi.org/10.4028/p-uch19d.

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Semisolid Al–Mg alloy strips were cast using high-speed twin-roll casting under very low roll loads to investigate the effect of low roll loads on surface cracking and center segregation of Mg. In the conventional twin-roll caster for aluminum alloys, the roll speed is usually less than 2 m/min, and the roll load is typically greater than 1 kN/mm to solidify the aluminum alloy and reduce casting defects. In the vertical type high-speed twin-roll caster, the roll speed can range from 10 to 90 m/min, and strips can be cast at roll loads below 500 N/mm, down to loads as low as 2 N/mm. Strips cast at 2 N/mm in this study did not completely solidify when released from the rolls; this means that the strips were semisolid. Al–Mg strips can be continuously cast without breaking when they are semisolid. The surface cracking and center segregation of these strips were compared with those of strips cast at a higher load of 88 N/mm. The effect of the small load on the presence of Mg at cross sections of the strip was investigated using etching with Weck’s reagent.

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Ragab, Khaled A., Mohamed Bouazara, Amine Bouaicha, and Hatem Mrad. "Materials Performance and Design Analysis of Suspension Lower-Arm Fabricated from Al-Si-Mg Castings." Key Engineering Materials 710 (September 2016): 315–20. http://dx.doi.org/10.4028/www.scientific.net/kem.710.315.

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The diversity of physical and mechanical properties of aluminum alloys leads to develop a variety of manufacturing processes including the semi-solid casting process. Fatigue failure is considered the most common problem occurred in automotive engineering applications by which the vehicle components, mainly suspension system parts, fail under conditions of dynamic loading. It is well known that the fatigue life of aluminum castings, mainly A357, is very sensitive to casting design as well as to casting defects and microstructure constituents. The fatigue characteristics of automotive lower suspension arm made of semi-solid A357 aluminum castings have been investigated using metallurgical and analytical approaches. The critical stress areas capable of initiating cracks during fatigue tests are detected by using fatigue experimental design for real part materials by the installation of strain gages on the suspension arm to calculate maximum stress; further more, analytical approach is applied using modelling software. Microstructure characteristics of the semisolid A357 under T6 heat treatment conditions are examined using scanning electron microscope. The results show that using the SEED casting technology (Swirled Enthalpy Equilibration Device) has an efficient effect on the mechanical and metallurgical characteristics of real part materials that are also affected by castings design.

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Pola, Annalisa, Lorenzo Montesano, Marcello Gelfi, Roberto Roberti, and Giovina Marina La Vecchia. "Aluminum Segregation in ZA27 Rheocast Alloy." Solid State Phenomena 217-218 (September 2014): 75–82. http://dx.doi.org/10.4028/www.scientific.net/ssp.217-218.75.

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Aluminum segregation in zinc alloys is a well-known problem during melting and casting. In molten Zn alloys, in fact, Al tends to float on the surface of the bath because of its lower density than zinc. The same problem also occurs during casting solidification, causing chemical gradients along part thickness and soundness problems. As a consequence, the use of high aluminum content zinc alloys, such as ZA27, can be limited.In this paper the effectiveness of rheocasting method on decreasing Al-segregation phenomenon in ZA27 was investigated. The slurry was obtained by using the ultrasound technique, starting from the fully liquid down to different solid fraction percentages. The metal was then cast into a permanent steel mold. The produced samples were completely characterized by metallographic analysis (optical and scanning electron microscope), to assess the microstructure modification induced by the treatment. Hardness tests were also performed to evaluate mechanical properties. For comparison, the same tests were performed on conventionally cast samples.The analyses show that the use of a semisolid alloy increases the homogeneity of the part in terms of hardness, chemical composition and microstructure; furthermore casting’s shrinkage porosity is significantly reduced.

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TANABE, Fumi, and Tetsuichi MOTEGI. "Characteristics of Thixoforming in Semisolid Continuous Casting Billet of Aluminum Alloys." Proceedings of the Materials and processing conference 2003.11 (2003): 291–92. http://dx.doi.org/10.1299/jsmemp.2003.11.291.

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Wang, Xiang, Tong Zhao, Di Tie, and Ren Guo Guan. "A Novel Process for Grain Refining and Semisolid Processing." Materials Science Forum 783-786 (May 2014): 148–54. http://dx.doi.org/10.4028/www.scientific.net/msf.783-786.148.

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A novel process for grain refining and manufacture of high quality semisolid slurries ofalloys was developed. The process was proven to refine metal grain remarkably, and the grain sizeof pure aluminum can be refined to the first grade of Chinese refining standard of pure aluminumGB/T 7946.4-1999 ref) . P rimary silicon and eutectic silicon in the hypereutectic Al-Si alloy can bealso effectively refined. This process was used to prepare the billets with small spherical grains orequiaxed grains of Al-6Si-2Mg, AZ91, AZ31 and hypereutectic Al-Si alloys successfully. The p ip es ,profi le s and wire s of 6201, AZ31 and AZ61 alloys were produced by continuous rheo-extrusion.The strips of AZ91, AZ31, and Mg-Sn alloys were prepared by rheo-rolling. As an innovativeprocessing technology with low cost and high efficiency, vibrating sloping plate melt treatment hasgood prospective application in many fields such as rheo-casting, rheo-extrusion, rheo-rolling,metal microstructure refinement, etc.

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Pola, Annalisa, Roberto Roberti, Ermanno Bertoli, and Disman Furloni. "Design and Production of New Aluminum Thixotropic Alloys for the Manufacture of Structural Components by Semisolid Die Casting." Solid State Phenomena 116-117 (October 2006): 58–63. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.58.

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Semi-solid processing is nowadays a powerful technology for the realization of structural components; in addition to the increase in their mechanical properties, due to the globular structure instead of the dendritic one, further developments are most likely to be expected from alloy chemical composition adjustments in order to achieve higher performances compared with the industrially used A356 and A357. Aim of this research is to try to set up new aluminium alloys for semisolid foundry applications, starting from the standard Al-Si system, at the base of all known casting processes. Different chemical compositions, based on either foundry or wrought Al alloys, have been investigated by means of computational thermodynamics (Pandat®), producing quantitative data about solidus-liquidus interval, solid fraction as a function of temperature, phase diagrams i.e. potential for age hardening, etc.. Some selected alloys, fitting the needs of good castability, proper concentration of hardening elements in the alpha phase and, obviously, easy production of feedstock material have been mechanically stirred by means of an experimental apparatus designed and self-constructed in the foundry laboratory of the university; the effect of different stirring tool configurations on the semi-solid state obtainment has also been assessed. Subsequently, the manufactured alloys have been reheated and cast into a simple die, properly designed, for the production of small samples. Microstructural investigations have been done on the stirred alloy (before and after re-heating), on the as cast and the heat treated samples to evaluate the efficiency of the designed system and of the defined alloys. Experimental tests on the processed alloys have been carried out by means of an instrumented crucible in order to verify the predicted thermodynamic properties supplied by simulation study (i.e. fs-temperature curve).

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Mao, Wei Min, Yue Long Bai, Song Fu Gao, and Guo Xing Tang. "Research on the Composite Slurry Preparation and Rheocasting of Aluminum Alloy." Solid State Phenomena 116-117 (October 2006): 410–16. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.410.

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The study on new rheoforming technologies of semisolid alloys has recently been one main subject interesting many professors, experts and industrials, and so many new methods about preparing semisolid alloy slurry and rheoforming process have been put forward. The semisolid slurry of AlSi7Mg alloy was prepared by being poured at a low superheat and stirred by an electromagnetic field at a low power for a short time, and then the slurry was further soaked for proper time and finally rheoformed into a key-shaped die cavity in this paper. The influence of slurry temperature, injection specific pressure and injection speed on the rheoforming process was also studied. The experimental results show that if AlSi7Mg alloy melt is poured at 630°C or 650°C and meanwhile stirred by an electromagnetic field at a low power for a short time, the most primary α-Al grains solidified in the slurry are spherical and only a few are rosette-like. If the slurry after made is then soaked in the liquidus-solidus range for some time, the ripening of primary α-Al grains is developed further and they become more spherical and larger. The experimental results also show that the slurry temperature, injection pressure and speed have a great influence on filling ability. The higher the slurry temperature, injection pressure and speed, the higher the slurry filling ability, and the shorter the core distance from the ingate, the more easily the die cavity is filled. With the given key-shaped casting, if only the slurry temperature should be equal to or more than 585,, or the injection pressure is equal to or more than 20 MPa, or the injection speed should be equal to or more than 1.73m/s, the key-shaped die cavity can be filled completely. The microstructural distribution in the casting is very homogeneous and it shows that the slurry prepared by the new method is very suitable for rheoforming and helpful to obtaining high quality castings.

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PIAO, LongYun, and Tetsuichi MOTEGI. "Solidified structure of a 5052 aluminum alloy obtained by semisolid casting." Journal of Japan Institute of Light Metals 55, no. 2 (2005): 86–90. http://dx.doi.org/10.2464/jilm.55.86.

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MOTEGI, Tetsuichi. "Semisolid Casting of Some Aluminum Alloys Using Inclined Cooling Plate and Their Thixoforming." Journal of the Japan Society for Technology of Plasticity 48, no. 560 (2007): 807–11. http://dx.doi.org/10.9773/sosei.48.807.

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Hu, Zhaohua, Qile Huo, Yaxin Chen, Manping Liu, and Xuefei Chen. "Improving Mechanical Property of Hyper-Eutectic Al-Si Alloys via Regulating the Microstructure by Rheo-Die-Casting." Metals 13, no. 5 (May 17, 2023): 968. http://dx.doi.org/10.3390/met13050968.

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The microstructure plays a key role in the mechanical properties of hyper-eutectic Al-Si alloys. In this study, we investigate the microstructural evolution of rheo-die-casting (RDC) on the Al-15Si-4Cu-0.5Mg alloy using a mechanical rotational barrel system. Our findings demonstrate that higher rotational speed and pouring temperature reduce the size and roundness of primary Si particles in the semisolid slurry. Additionally, during RDC, the dendritic aluminum matrix and skeletal iron-containing inter metallics are sheared off, leading to a more uniform and dispersed Al2Cu phase. Ultimately, our rheo-diecasting results indicate the formation of a near globular aluminum matrix, fine primary Si particles, and a homogeneous Al2Cu phase, thus highlighting the efficacy of this processing method for improving the microstructure and properties of the Al-15Si-4Cu-0.5Mg alloy. We suggest that these results hold promise for enhancing the quality of aluminum-based alloys in various industrial applications.

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Mahathaninwong, Narissara, Sirikul Wisutmethangoon, Thawatchai Plookphol, and Jessada Wannasin. "Influence of Solution Heat Treatment on Microstructures of Semisolid Cast 7075 Aluminium Alloy." Advanced Materials Research 339 (September 2011): 371–74. http://dx.doi.org/10.4028/www.scientific.net/amr.339.371.

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Influence of temperature and time of solution heat treatment on the microstructures of rheo-casting 7075 aluminium alloy produced by a novel technique, the Gas Induced Semi Solid (GISS) technique, had been investigated in this study. The microstructure of the as-cast specimens mainly consisted of matrix-α (Al) and grain boundary (GB)-eutectic phase (α-Al + Mg(Zn,Cu,Al)2). After solution heat treatment at 480 °C for 1 h, MgZn2 phase at the grain boundary was observed to have dissolved and coarse black particles of Mg2Si were observed to form in the matrix. In comparison, when solutionizing temperature of 450 °C was applied, it took 4 h of solution treatment time in order to dissolve the same portion of GB phase and MgZn2 phase, and coarse black particles of Mg2Si were found to form in the 8 h solution treated sample.

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Qi, Ming Fan, Yong Lin Kang, and Quan Quan Qiu. "Industrialized Application of Rheo-HPDC Process for the Production of Large Thin-Walled Aluminum Alloy Parts." Solid State Phenomena 285 (January 2019): 453–58. http://dx.doi.org/10.4028/www.scientific.net/ssp.285.453.

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A simplified and efficient process, namely air-cooled stirring rod (ACSR), was proposed to prepare semisolid slurry of aluminum alloys. An advanced integrated rheological high pressure die-casting (Rheo-HPDC) technology was established by combining the ACSR equipment with HPDC machines to produce high quality aluminum alloy products. Microstructures, surface qualities, mechanical properties, corrosion resistances and thermal conductivities of the Al-8Si alloy parts prepared by Rheo-HPDC were investigated and compared to those prepared by traditional HPDC. The results indicated that the Rheo-HPDC process can prepare aluminum alloy parts in which the primary particles are fine and spherical, and there is few shrinkage porosity. Multifarious high quality large thin-walled aluminum alloy parts, such as filter shells, cooling shells, antenna crates and mounting brackets for communication, were produced by the process. Rheo-HPDC alloys showed improved surface quality to those formed by traditional HPDC, and the surface roughness is small and avoid employing CNC to surface finish. Also, compared with HPDC alloys, the alloys prepared by Rheo-HPDC have an increased mechanical properties and thermal conductivity due to high density and refined microstructure. Furthermore, Rheo-HPDC aluminum alloys indicated a remarkable improvement in corrosion resistance as shown by the results of electrochemical and weight loss experiments.

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TANABE, Fumi, Tetsuichi MOTEGI, and Eiji SUGIURA. "Semisolid continuous casting of 6070 and 7075 aluminum alloys using an inclined cooling plate." Journal of Japan Institute of Light Metals 53, no. 7 (2003): 290–94. http://dx.doi.org/10.2464/jilm.53.290.

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TANABE, Fumi, Tetsuichi MOTEGI, and Eiji SUGIURA. "Characteristics of thixoforming in semisolid continuous casting billets of 6070 and 7075 aluminum alloys." Journal of Japan Institute of Light Metals 53, no. 8 (2003): 327–30. http://dx.doi.org/10.2464/jilm.53.327.

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Kang, Yong Lin, Liu Qing Yang, Ren Bo Song, Fan Zhang, and Tao Tao. "Study on Microstructure-Processing Relationship of a Semisolid Rheocasting A357 Aluminum Alloy." Solid State Phenomena 141-143 (July 2008): 157–62. http://dx.doi.org/10.4028/www.scientific.net/ssp.141-143.157.

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An improved and self-developed semisolid preparing and rheomoulding device — rotating barrel rheomoulding machine (RBRM) for light alloys in laboratory is introduced in this paper. It mainly consists of a melting furnace, a shearing system with two relative-rotating conical barrels, a central temperature control unit, gas protection system and a die-casting system. Microstructure-processing relationship of A357 aluminum alloy obtained by the RBRM process is investigated by different intensity of turbulence and different shear rate. The experimental results show that the improved RBRM is capable of eliminating coarse dendrites, and producing small and spherical solid particles uniformly distributed in a eutectic matrix. In addition, the process can eliminate entrapped gas and reduce fine shrinkage pores in the specimens as well. Compared with the original self-developed device in our laboratory, the improved equipment has the following advantages: accurate control of stirring temperature; small volume and convenient manipulation; fine and spherical solid particles, chemical and microstructural uniformity throughout the specimens and so on.

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Ouriev, Boris. "Rheology and Rheometry of Aluminum Alloys: Influence of Shear and Vibration on Aluminum Flow Properties." Solid State Phenomena 116-117 (October 2006): 558–64. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.558.

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Understanding of flow properties and flow effects of liquid and semisolid aluminum became a key solution for know-how of casting process. Therefore such properties must be characterized a priory to layout of flow process parameters in order to predict structure formation of aluminum in flow. In order to reach target of material characterization it becomes essential to analyze materials under as close to real process conditions as possible. This task was solved by strong modification of commercial rotational rheometer and application of high-resolution temperature control. Besides understanding the flow properties it is essential to find the way of interactive structure control during flow process. Therefore controllable effects were generated and studied with the help of structure related rheological flow properties. For triggering structure formation an influence of mechanical vibration on flow properties of highly concentrated semisolid alloy is explored in this work. For that experimental set-up was designed and adapted to conventional rotational rheometer with precise rheological characterization capability. Priory to fundamental experiments with highly concentrated aluminum suspension a number of calibration tests were performed. Also prediction of wall slippage in shear flow under vibration was evaluated. Analysis of boundary conditions shows that no considerable side effects were present during shear experiment under vibration. The research reveals precise detection of transition temperatures with the help of steady and transient shear viscosity measurement besides selective measurement of full rheological curves within liquid and semisolid state temperature range. Rheological characterization was performed under shear flow conditions with and without presence of orthogonal to flow direction mechanical vibration. It was found that superposition of mechanical vibration and shear flow radically decreases shear viscosity but only in semisolid state. Liquid state rheological properties shows structural behavior but kept insensitive to application of mechanical vibration. For semisolid alloys, comparison between reference shear viscosities at specified shear rates and those measured under vibration shows considerable differences in flow properties. Conversion of concentrated suspension from strongly shear-thinning to almost Newtonian flow behavior is reported here. It is suggested to relate such phenomenon to non-equilibrium between structure formation and disintegration under vibration and hydrodynamic forces of shear flow. Influence of vibration on structure formation was also well observed during measurement of solidification process. Comparison to reference data shows how sensitive structure of concentrated suspension is to vibration in general and especially during solidification phase. The reveled effects and observations provide a solid bases for further fundamental investigations of structure formation regularities in flow of any highly concentrated systems.

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Jarfors, Anders E. W., Diego Rigovacca, Mostafa Payandeh, Magnus Wessen, Salem Seifeddine, and Per Jansson. "Influence of Process Parameters on Surface Appearance and Roughness of a Low Si Containing Al-Alloy, in Semisolid Casting." Solid State Phenomena 217-218 (September 2014): 318–24. http://dx.doi.org/10.4028/www.scientific.net/ssp.217-218.318.

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The visual appearance and surface roughness were experimentally investigated in industrial scale for a low silicon containing aluminium alloy cast in semisolid state integrated with HPDC machine. A visual comparative technique and surface roughness in the form of the Rq value were used to evaluate the surface appearance and the surface roughness respectively. The results were investigated statistically to find significant models. It was shown that high quality appearance, following a comparative scale, was possible using high die temperature and high injection speed. It was also found that improving the surface roughness will deteriorate the visual appearance.

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A. Razak, N., A. H. Ahmad, and M. R. Maarof. "Thermal Profile and Microstructure of Wrought Aluminium 7075 for Semisolid Metal Processing." International Journal of Automotive and Mechanical Engineering 17, no. 2 (July 2, 2020): 7842–50. http://dx.doi.org/10.15282/ijame.17.2.2020.03.0584.

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Thermal analysis (TA) is a non-damaging and quick method to check the molten metal’s condition preceding to casting. This paper aims to present the relationship between fraction solid and temperature by utilising cooling curve analysis (CCA), to acquire correct processing parameters for wrought aluminium 7075 in semisolid condition. An induction furnace was used to heat a graphite crucible containing wrought aluminium 7075 alloy up to the temperature of 750 °C. A calibrated Chromel-Alumel K-type thermocouple was placed at the centre of the crucible and was submerged to 15 mm in the melt. The solidification temperature and time were measured by Data Logger GL-220. Normal, intermediate, and high cooling rate conditions were achieved when the crucible was left in an open atmosphere, in an open atmosphere with additional minimum airflow, and in an open atmosphere with the maximum airflow, respectively. It was found that the normal cooling rate was estimated at 2.23 °C/s, the intermediate cooling rate was calculated at 2.88 °C/s while the high cooling rate was recorded at 3.20 °C/s. The increase in cooling rate conditions has a significant effect on the changes of phases during solidification process where it leads to the decreased in liquidus, eutectic and solidus temperature. The microstructure feature was found to have a significant difference with the variation of cooling rates where higher cooling rate led to smaller primary grain size.

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de Paula, Leandro Cássio, Shun Tokita, Kota Kadoi, Hiroshige Inoue, and Eugênio José Zoqui. "Analysis of the 355 Aluminium Alloy Microstructure for Application in Thixoforming." Solid State Phenomena 285 (January 2019): 277–82. http://dx.doi.org/10.4028/www.scientific.net/ssp.285.277.

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The 355 aluminium alloy is known to have excellent thermodynamic characteristics that render it suitable as a raw material for rheocasting and thixoforming. However, besides the controllable transition from solid to liquid phase, the refined microstructure required in the semisolid range is one of the key factors with a strong influence on the rheology of the material. This paper intends to analyse the in situ behaviour of the microstructure, in terms of morphological change, using high-temperature laser scanning confocal microscopy. The 355 alloy was prepared via conventional casting, and refined with a 30-s exposition via ultrasonic melt treatment (UST - 20 Hz, 2 kW). The material was reheated up to the thixoforming target temperature of 595 °C at which it was maintained for 0, 30, 60, 90, and 120 s, after which all the samples were cooled in water. The samples subjected to UST prior to the heat treatment were more refined in terms of microstructural evolution; they exhibited reduction in grain size (~107 ± 16 μm), smallest primary phase particle size (~81 ± 7 μm), and high circularity shape factor (~0.59 ± 0.19 μm). In situ observation methods were employed to analyse evolution mechanisms such as Ostwald ripening and coalescence.

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Srivastava, Ashish Kumar, and Rohit Srivastava. "To Investigate Mechanical Properties of Al-based Composite Reinforced with Waste Product." Journal of Futuristic Sciences and Applications 5, no. 2 (2022): 81–89. http://dx.doi.org/10.51976/jfsa.522211.

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The most common use for aluminium metal matrix composite, or AMMC, is variety of industrial submissions, including those in aerospace, automotive, marine, and sports industries, amongst many others. The most important reinforcing components for manufacturing AMMC are SiC, aluminium oxides, MnO, graphene, and carbon nano tubes, since these components are often used in practice. This article’s goal is to build AMMCs that are reinforced with Silicon carbide (SiC) and Alumina (Al2O3). In order to make AMMC, a procedure known as stir casting is used. Since the last several years, increased attention has been placed on the preparation of AMMCs employing agro waste as reinforcing materials. Examples of such waste are rice husk and/or SiC. As soon as the Al-matrix material has been melted using this method and churned violently, reinforcing material is added to one side of this vortex, creating a spherical structure. The AMMCs may be prepared via a procedure called stir casting, which involves a violent and whirling motion. In the beginning, the furnace is used to melt the aluminium alloy (AA3105) when the metal is in a semisolid state. The reinforcing materials, also known as SiC and Alumina (Al2O3), are warmed to temperatures of 260 and 220 degrees Celsius, respectively. According to the findings of AMMC, tensile strength and hardness of material both rose by 22.41 percent and 45.5 percent, respectively, when they were reinforced with 4.75 weight percent of each kind of reinforcement (SiC, Al2O3, and 1 percent Cr). When 1 percent Cr, 4.75 weight percent SiC, and 4.75 weight percent Al2O3 of composite material are used.

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Eslami, Maryam, Flavio Deflorian, and Caterina Zanella. "Electrochemical Behavior of Conventional and Rheo-High-Pressure Die Cast Low Silicon Aluminum Alloys in NaCl Solutions." CORROSION 75, no. 11 (September 18, 2019): 1339–53. http://dx.doi.org/10.5006/3254.

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The electrochemical behavior of a low silicon aluminum alloy cast by the conventional and rheo-high-pressure die cast processes is evaluated using polarization test and electrochemical impedance spectroscopy in 0.01 M, 0.05 M, 0.1 M, and 0.6 M sodium chloride solutions. Compared to the conventional high-pressure die cast process, rheocasting introduces some alterations in the microstructure including the presence of aluminum grains with different sizes, formed at different solidification stages. According to the results of the anodic polarization test, conventional cast and rheocast samples show similar breakdown potentials. However, the rheocast samples present enhanced oxygen reduction kinetics compared to the conventional cast sample. Based on scanning electron microscopy examinations, localized microgalvanic corrosion is the main corrosion mechanism for both alloys and it initiates at the interface of aluminum with iron-rich intermetallic particles which are located inside the eutectic regions. The corrosion further develops into the eutectic area. Although the rate of the cathodic reaction can be influenced by the semisolid microstructure, according to the results of anodic polarization and electrochemical impedance spectroscopy tests, the corrosion behavior is not meaningfully affected by the casting process.

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Kolahdooz, Amin. "Investigation of the hardness improvement for Al-A380 alloy using the controlled atmosphere in the mechanical stirring casting method." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 233, no. 2 (May 4, 2018): 225–33. http://dx.doi.org/10.1177/0954408918773526.

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This work studied the semisolid (SSM) Al-A380 alloy formed by mechanical stirring under the circumstances of controlled atmosphere with argon gas. The A380 aluminium alloy produced due to this process can be used instead of the forging processes or die casting with better mechanical properties. In this paper, first, the effects of the solid fraction, the stirring speed and the mold temperature on the hardness and microstructure are studied using a mechanical stirrer. Then some tests such as XRD and ultrasonic test are done to investigate the effect of using the controlled atmosphere system. By optimizing the forming parameters and with the breaking of primary a phase dendrites, the microstructure will be changed to the spherical form, therefore the mechanical properties will be improved. The results showed that the hardness of the billets has increased significantly due to the uniform grains distribution at the condition of 580 ℃ stirring temperature, 300 r/min stirring speed and mold temperature of 100 ℃. Also, the process properly optimized with the controlled atmosphere. In this condition, the results illustrated that the mechanical properties of the alloy increased around 30%.

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Wenzelburger, Martin, Martin Silber, and Rainer Gadow. "Manufacturing of Light Metal Matrix Composites by Combined Thermal Spray and Semisolid Forming Process – Summary of the Current State of Technology." Key Engineering Materials 425 (January 2010): 217–44. http://dx.doi.org/10.4028/www.scientific.net/kem.425.217.

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The demand for lightweight structures in the automotive and aerospace industry increases permanently, and the importance of lightweight design principles is also increasing in other industrial branches, aiming towards improved energy efficiency and sustainability. Light metals are promising candidates to realize security relevant lightweight components because of their high specific strength; and amongst them, aluminum alloys are the most interesting materials due to their high plasticity and strain to failure, good processability, passivation in oxygen containing atmosphere, and low cost. However, for many applications, their stiffness as well as strength and fatigue behavior at elevated temperature are insufficient. Metal matrix composite (MMC) formation by integration of reinforcements in the form of continuous or discontinuous (short) fibers can yield a high increase in the alloys’ specific mechanical properties at room temperature and at elevated temperature. The integration of fibers with conventional manufacturing techniques like squeeze casting, hot pressing or diffusion bonding leads to restrictions in the component’s geometry. Moreover, these techniques result in elevated process costs mainly caused by long cycle times and the need of additional protective fiber coatings. In the present paper, an alternative method for the manufacturing of aluminum matrix composites is described, combining thermal spraying and semisolid forming (thixoforging) technologies for the formation of fiber prepregs and subsequent forming with simultaneous densification. Therefore, prepregs with the matrix alloy as a thick surface coating on the reinforcement fibers are manufactured in a fast, automated coating process, while reheating, densification and shaping are performed in a separate process, allowing an optimization of both processes towards cycle times and resulting material properties. Continuous fiber and short fiber reinforced aluminum matrix composites are manufactured using woven or parallel arranged continuous fibers, or short fibers as a fleece or fiber paper material. For the coating process, twin-wire electric arc spraying is applied as a well established, cost efficient thermal spray technology. The coating process is optimized towards microstructure of the matrix alloy prior to semisolid forming, which requires a globular alloy microstructure, and reduced fiber damage during the high-temperature liquid melt deposition. The thermally sprayed fine-grained matrix material enables semisolid forming at liquid contents of 40-60 vol% of the alloy, with short flow paths, reduced mechanical loads and short cycle times. Thus, limited fiber damage and residual stresses will occur, leading to good mechanical material properties. A production line for industrial-scale coating of fiber fabric coils in a continuous process is introduced in order to provide prepregs of various fiber-reinforcement materials and fiber architectures; moreover, a winding equipment for simultaneous fiber winding and coating is presented that enables local reinforcement for components with adapted, tailored composite material design.

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Qiu, Zhi Yan, Bing Zhou, Shuai Lu, Ke Ping Chen, Chun Xu, and Zhan Yong Wang. "Microstructures, Simulations and Solidification Behaviors of A356 Semisolid Aluminium Alloy Prepared by Stirring Integrated Transfer-Heat Technology under Different Cooling Mediums." Solid State Phenomena 330 (April 12, 2022): 3–10. http://dx.doi.org/10.4028/p-9i8e01.

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Based on the theory of grain refinement, the microstructures and simulations of A356 semi-solid aluminum alloy under different cooling mediums were studied. The experiment and simulation results show that water cooling is better than any other cooling mediums. Combined with the simulation of stirring and heat dissipation in SIT device, the changes of temperature field and solid fraction of the melt were studied to help understand the nucleation, growth and solidification behavior under the SIT process. During the process, the temperature field of the melt becomes relatively uniform from a larger temperature gradient and the continuous cooling speed is increased. The results also indicate that compared with traditional casting, the microstructure cooled by water are composed of refined rosiness and nearly spherical particles. With the increase of cooling degree, the average grain size decreased from 206μm to 186μm. The solid fraction increases from 4.4% to 12.2% under the no-cooling and air-cooling conditions, while it is more uniform, increasing from 5.1% to 8.8% due to the water cooling.

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Qi, Mingfan, Yonglin Kang, Jingyuan Li, Zhumabieke Wulabieke, Yuzhao Xu, Yangde Li, Aisen Liu, and Junchen Chen. "Microstructures refinement and mechanical properties enhancement of aluminum and magnesium alloys by combining distributary-confluence channel process for semisolid slurry preparation with high pressure die-casting." Journal of Materials Processing Technology 285 (November 2020): 116800. http://dx.doi.org/10.1016/j.jmatprotec.2020.116800.

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Nakamura, Ryoji, Kenta Takahashi, and Masahiko Ikawa. "Aluminum Alloy Strips Casting Using an Unequal Diameter Twin Roll Caster." Materials Science Forum 449-452 (March 2004): 145–48. http://dx.doi.org/10.4028/www.scientific.net/msf.449-452.145.

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An unequal diameter twin roll caster was devised in order to increase productivity of the strip. This caster could cast the strip thicker than 6mm at the speed of 5m/min. The feature of this caster is that the lower roll was four times larger than the upper roll. The solidification length of the strip could be set longer easily than the conventional twin roll caster for aluminum alloy. Lowsolidification rate semisolid casting and low superheat casting were adopted. These were effective to increase the casting speed without decreasing the thickness of the strip. In the present study, the unequal diameter twin roll caster was designed and assembled. The test castings were operated and the characteristics of this caster were shown.

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Nakamura, Ryoji, T. Asai, Hisaki Watari, and Shinji Kumai. "Casting of Aluminum Alloy Bar by Semisolid Roll Casting." Solid State Phenomena 141-143 (July 2008): 295–300. http://dx.doi.org/10.4028/www.scientific.net/ssp.141-143.295.

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Rheo-casting of 4045 aluminum alloy bar was operated using an unequal diameter twin roll caster and a cooling slope. The semisolid slurry was made by the cooling slope. The thickness of the bar was 12 mm and width was 100mm. The casting speed was 1m/min. Quantity of the melt poured on the cooling slope was important to make sound bar. The primary crystal became spherical, and its size was about 40μm.

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HAGA, Toshio, Hisaki WATARI, and Shinichi NISHIDA. "Casting of Aluminum Alloy Strip Using Semisolid Condition." Proceedings of the Materials and processing conference 2019.27 (2019): 432. http://dx.doi.org/10.1299/jsmemp.2019.27.432.

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MOTEGI, Tetsuichi, and Long Yun PIAO. "2330 Semisolid continuous casting of 5052 aluminum alloy." Proceedings of the JSME annual meeting 2005.1 (2005): 721–22. http://dx.doi.org/10.1299/jsmemecjo.2005.1.0_721.

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48

Nakamura, Ryoji, Hideki Inui, Hisaki Watari, and Shinji Kumai. "Semisolid Roll Casting of Aluminum Alloy Strip and Its Properties." Solid State Phenomena 116-117 (October 2006): 379–82. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.379.

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A356 was cast into the strip by the semisolid strip casting using an unequal diameter twin roll caster. This process was one of the rheocasting. The semisolid slurry was made by a cooling slope. Solid fraction was about 5%. The casting speed was 20 m/min, and the thickness was 4.4 mm. The as-cast strip could be cold rolled down to 1 mm. The result of tension test of 1mm-thickness-T4 heat-treated strip was as below. Tensile stress was 223 MPa, 0.2 proof stress was 123 MPa and elongation was 21.8%. Deep drawing could be operated to 1 mm-thickness T4 sheet, and L.D.R was attained to 2.0. In some condition, 180 degrees bending could be operated without crack at outer surface. These results mean that semisolid roll cast A356 strip may be able to use for press forming.

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Haga, Toshio, Shinichiro Imamura, Ryota Miwa, and Hiroshi Fuse. "Semisolid Casting and Die Casting of Al-4.8%Mg-2%Si Alloy." Solid State Phenomena 327 (January 10, 2022): 172–77. http://dx.doi.org/10.4028/www.scientific.net/ssp.327.172.

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An aluminum alloy, Al–4.8%Mg–2%Si, was cast by die casting and thixocasting, and the properties of the cast specimens were investigated. When the poured molten metal temperature was lower than 640 °C during die casting, it was lower than the liquidus temperature, and the metal became a semisolid slurry in the sleeve of the die casting machine; this fulfills the conditions for rheocasting. A tension test was conducted to investigate the effects of semisolid casting on the mechanical properties of Al–4.8%Mg–2%Si. The ultimate tensile strength and elongation of the ingots cast by die casting and rheocasting were affected by the size of ingot. When the ingot had a circular base of 4.5 mm diameter, the ultimate tensile strength and elongation were excellent; however, when the cross section of the ingot was a square with a side length of 20 mm, the tensile strength and elongation were inferior. The thixocasting was conducted using square ingots with a side length of 20 mm, and the tensile strength and elongation were poor in this case as well. The results of this study demonstrate that semisolid casting cannot improve the mechanical properties of Al–4.8%Mg–2%Si ingots with a high thickness. Semisolid casting cannot produce fine-grained Mg2Si, and the mechanical properties of the material could not be improved by this casting method.

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Haga, Toshio, Takuya Yamashiki, Hisaki Watari, and Shinichi Nishida. "Burr Formation in Casting Using Vertical-Type High-Speed Twin-Roll Caster." Key Engineering Materials 846 (June 2020): 146–51. http://dx.doi.org/10.4028/www.scientific.net/kem.846.146.

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The mechanism and region of burr formation in casting using a vertical-type high-speed twin-roll caster were investigated using a side-dam plate with a window. A383, an aluminum alloy typically used for casting due to its excellent fluidity at semisolid condition was used. The solid fraction of the semisolid metal ejected from the window was low. When solid metal was ejected from the window, no burr formed. The results suggest that a burr formed when the semisolid metal was ejected in gap between the side-dam plate and the side surface of a roll. The semisolid metal was ejected near the point where the semisolid metal on the two rolls met.

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Journal articles on the topic 'Aluminium Alloys - Semisolid Die Casting'

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