Articoli di riviste: "Aluminum alloys. Mechanical engineering. Testing"

1

Sharapova, Dinaida M., Mikhail G. Sharapov e Nikolay I. Sharonov. "Structure Formation of Butt Joints Made of Aluminum Alloys to Ensure the Quality of Mechanical Engineering Products". Materials Science Forum 1022 (febbraio 2021): 119–26. http://dx.doi.org/10.4028/www.scientific.net/msf.1022.119.

Testo completo

Abstract (sommario):

The article discusses the problems of ensuring high-quality formation and normative properties of butt joints of the 1560M and 1980T1 (AMg6 and B48) aluminum alloys as applied to engineering. A method is proposed for joining materials by means of EBW using an electron beam sweep. Homogeneous and dissimilar joints have been investigated, heat treatment of joint from the 1980T1 alloy and a dissimilar joint from the 1560M + 1980T1 alloys is recommended. The paper also presents the results of mechanical properties testing, the corrosion resistance and the delayed fracture tests. A welding technology that makes it possible to obtain high-quality butt-welded joints from aluminum alloys in thicknesses up to 40 mm has been developed and implemented.

Gli stili APA, Harvard, Vancouver, ISO e altri

2

Petersen, DR, RE Link, H. Shi, AJ McLaren, CM Sellars, R. Shahani e R. Bolingbroke. "Hot Plane Strain Compression Testing of Aluminum Alloys". Journal of Testing and Evaluation 25, n. 1 (1997): 61. http://dx.doi.org/10.1520/jte11326j.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

3

JOPEK, MIROSLAV, MILAN FOREJT e MARTIN HARANT. "MECHANICAL PROPERTIES OF ALUMINIUM ALLOYS AT HIGH STRAIN RATE". MM Science Journal 2021, n. 2 (2 giugno 2021): 4505–11. http://dx.doi.org/10.17973/mmsj.2021_6_2021050.

Testo completo

Abstract (sommario):

The split Hopkinson's pressure bar test is a part of a group of testing methods used to determine dynamic behavior of various materials in an interval of strain rate from 100 s-1 to 103 s-1. The article describes the practical application of the testing method for aluminum alloy EN AW 6082. This alloy is used for cold-extruded parts (components of car airbags). Since the strain rate of cold forming technologies reaches up to 1000 s-1, it is necessary to determine the material´s behavior at these strain rate values.

Gli stili APA, Harvard, Vancouver, ISO e altri

4

Petersen, DR, RE Goforth e MN Srinivasan. "Testing the Superplastic Flow Characteristics of Advanced Aluminum Alloys". Journal of Testing and Evaluation 21, n. 1 (1993): 36. http://dx.doi.org/10.1520/jte11739j.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

5

DeGaspari, John. "Making the Most of Aluminum Scrap". Mechanical Engineering 121, n. 11 (1 novembre 1999): 71–73. http://dx.doi.org/10.1115/1.1999-nov-3.

Testo completo

Abstract (sommario):

This article highlights features of a process under-development that aims to recover wrought alloys for high-value applications. Chemically etched wrought aluminum scrap pieces have been separated into their respective alloy families using an optical identification system that is being developed by Alcoa. The technique has successfully completed proof-of-concept testing at Pacific Northwest National laboratory. One method of separating the mix of wrought aluminum into its alloy families combines chemical etching with an optical technique to sort the aluminum by color. John Green, vice president of technology of The Aluminum Association, believes these technologies will give automotive companies an incentive to commit to aluminum for sheet applications by ensuring that recycling wrought aluminum into higher-value applications is feasible. According to an expert, since processing recycled aluminum takes only 5 percent of the energy required to work from primary ingot, using recycled aluminum makes sense for automobiles.

Gli stili APA, Harvard, Vancouver, ISO e altri

6

Shi, De Quan, Zhi Wei Gao, Gui Li Gao, Xu Dong Wang e Hui Ying Tang. "Influence of Quenching Parameters on Mechanical Properties of 7075 Aluminum Alloy". Advanced Materials Research 217-218 (marzo 2011): 238–42. http://dx.doi.org/10.4028/www.scientific.net/amr.217-218.238.

Testo completo

Abstract (sommario):

By using the universal mechanical testing machine and SEM, the influence of quenching parameters on the mechanical properties of 7075 aluminum alloy has been studied, and the optimal quenching parameters have been got. The experimental results show that the temperature range of the quenching treatment is too wide. However, the over-burning will occur when the temperature is above 490°C. So the optimal quenching temperature is from 465°C to 475°C. The water temperature and the transfer time are below 40°C and 30s, respectively. The time interval between the quenching and aging treatment is found to have little influence on the mechanical properties of 7075 aluminum alloys.

Gli stili APA, Harvard, Vancouver, ISO e altri

7

Friedman, R., J. Kennedy e D. Royster. "Analysis and Compression Testing of 2024 and 8009 Aluminum Alloy Zee-Stiffened Panels". Journal of Engineering Materials and Technology 116, n. 2 (1 aprile 1994): 238–43. http://dx.doi.org/10.1115/1.2904279.

Testo completo

Abstract (sommario):

Zee-stiffened compression test panels, fabricated with dispersion-strengthened, high-temperature 8009 aluminum alloy sheet, were evaluated to determine the alloy’s feasibility for compression-critical applications. A compression panel design configuration was obtained using a strength analysis program that predicts the post-skin buckling strength of flat or curved-skinned, metallic-stiffened structure. Three short-column panels were tested to failure at room temperature: (a) a baseline riveted panel fabricated with 2024-T62 aluminum zee stringers and a 2024-T81 aluminum skin, (b) a riveted panel fabricated with 8009 aluminum zee stringers and skin, and (c) a resistance spot-welded panel fabricated with 8009 aluminum zee stringers and skin. The 8009 alloy exhibited pronounced, compressive strength anisotropy, necessitating panel orientation to take advantage of the higher compressive yield in the sheet transverse direction. Compression test results were in good agreement with the predicted compression allowables since they were within 5 percent of the test strength. The 8009 aluminum riveted panel exhibited superior skin buckling resistance and failed in the wrinkling mode, as predicted, at a load approximately 15 percent higher than that of the baseline 2024 panel. The spotwelded 8009 panel did not fail in the wrinkling mode since the spot welds failed in tension shortly after the skin locally buckled. The latter test indicates that the spot welded skin-stringer combinations should not be used above the buckling stress. Due to its excellent microstructural stability at elevated temperatures, high-temperature compression panels of 8009 alloy offer potential weight savings of 25 percent compared with conventional aluminum alloys.

Gli stili APA, Harvard, Vancouver, ISO e altri

8

Wang, Yuan Qing, Huan Xin Yuan e Yong Jiu Shi. "Mechanical and Fatigue Performance Tests of Cast Aluminum Alloy ZL111 Adopted in Structure". Advanced Materials Research 168-170 (dicembre 2010): 1961–69. http://dx.doi.org/10.4028/www.scientific.net/amr.168-170.1961.

Testo completo

Abstract (sommario):

Characteristics of aluminum alloys such as light weight, high strength-to-weight ratio and favorable corrosion resistance have brought about a bright application prospect in building structures. Wrought alloys are applicable to common beams and columns, while casting alloys can be fabricated as connectors in point-supported glass curtain wall and joints in spatial latticed structures on account of easy implement of moulding. Because of high strength, outstanding castability and remarkable mechanical properties after heat treatment, ZL111 in aluminum-silicon alloys is regarded as a desirable option. However, aluminum alloys are non-linear materials and their properties vary with casting and heat treatment modes. It is the well-marked distinction between aluminum alloy and ordinary carbon steel that special study on mechanical and fatigue performance is required. ZL111 raw materials were selected, with alloying agent and fabrication processes meeting the requirement of GB/T 1173-1995 standard. After T6 heat treatment process, test coupons were obtained by machining from raw materials. By utilization of electronic universal testing machine and cryogenic box, tensile tests at room temperature and low temperatures were performed. High-circle fatigue tests were carried out to obtain the fatigue performance of the material. Scanning electron microscope (SEM) was introduced to observe morphology of tensile and fatigue fractures. The tests revealed the relationship between mechanical property index and temperature, which indicated that the ZL111-T6 would increase in strength and plasticity. The microstructure of fractures validated and explained the macroscopic results. Furthermore, material strength at room temperature or low temperatures, stiffness and fatigue performance could satisfy bearing and normal serviceability requirement. Because of non existence of ductile-brittle transition temperature, superior corrosion resistance and outstanding castability, ZL111-T6 material is prone to fabricate complicated elements and joints withstanding cryogenic environment instead of carbon steel.

Gli stili APA, Harvard, Vancouver, ISO e altri

9

Zaharia, I. I., e Virgil Geamăn. "Practical Aspects Regarding to Thixoforming Process Applied to Aluminum Alloys". Advanced Materials Research 23 (ottobre 2007): 161–64. http://dx.doi.org/10.4028/www.scientific.net/amr.23.161.

Testo completo

Abstract (sommario):

The paper presents some experimental data about the thixoforming process applied to different aluminum alloys very used in the Romanian machine building industry. From many procedures for obtaining the semisolid slurry described in the paper, based on specialized literature [2, 3, 4] in particular, the accent is given to choose the mechanical mixture in the overheated mould until it reached the liquid alloy temperature. The main results are based on reducing of stirring time for increasing the benefits of the new technology. All procedures and results are described in the paper and also some specific conclusions are given. The experimental data of the research, were obtained in the specific testing laboratory from Transilvania University of Brasov.

Gli stili APA, Harvard, Vancouver, ISO e altri

10

Masyrukan e Agung Setyo Darmawan. "Influence of Artificial Aging in Aluminum Silicon Alloy". Materials Science Forum 1029 (maggio 2021): 9–14. http://dx.doi.org/10.4028/www.scientific.net/msf.1029.9.

Testo completo

Abstract (sommario):

One of the techniques to increase the hardness of aluminum alloy is by aging process. The aging process includes natural aging and artificial aging processes. This study aims to investigate the effect of artificial aging on the hardness of aluminum silicon alloys. Artificial aging is carried out at two temperature variations, namely 150 and 200 °C. Metallographic test using optical microscopy and scanning electron microscopy were performed to observe the microstructure and deposits of silicon. Investigation of the constituent elements of aluminum silicon was carried out using the Energy Dispersive X-Ray Spectroscopy technique. The mechanical properties of aluminum silicon alloys examined were hardness before aging and hardness after artificial aging at temperatures of 150 and 200 °C. Hardness testing is conducted by Rockwell B hardness testing. The hardness test results showed that the hardness before the aging process was 61.1 HRB, the hardness after artificial aging at 150 °C was 69.11 HRB and the hardness after artificial aging at 200 °C was 80.36 HRB. There was an increase in hardness after the artificial aging process was carried out.

Gli stili APA, Harvard, Vancouver, ISO e altri

11

Petersen, DR, RE Link, L. Schra e RJH Wanhill. "Further Evaluation of Automated Stress Corrosion Ring (ASCOR) Testing of Aluminum Alloys". Journal of Testing and Evaluation 27, n. 3 (1999): 196. http://dx.doi.org/10.1520/jte12062j.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

12

Dariusz, Leśniak. "New original method and device for testing aluminum alloys susceptibility for extrusion welding". Archives of Civil and Mechanical Engineering 18, n. 4 (settembre 2018): 1491–505. http://dx.doi.org/10.1016/j.acme.2018.06.004.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

13

Wolfenden, A., e PW Beaver. "J-Integral Testing of Aluminum Alloys: A New Technique for Marking Crack Fronts". Journal of Testing and Evaluation 15, n. 6 (1987): 350. http://dx.doi.org/10.1520/jte11033j.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

14

Masroor, Zunair, Ahsan Abdul Rauf, Faisal Mustafa e Syed Wilayat Husain. "Crack Repairing of Aluminum Alloy 6061 by Reinforcement of Al₂O₃ and B₄C Particles Using Friction Stir Processing". Key Engineering Materials 875 (febbraio 2021): 238–47. http://dx.doi.org/10.4028/www.scientific.net/kem.875.238.

Testo completo

Abstract (sommario):

Crack repairing of aluminum alloys is done using conventional welding techniques or mechanical methods, which results in the redundancy of mechanical properties due to defects formation. Friction Stir Welding/Processing (FSW/FSP) is a solid-state joining technique which is used to join various different similar and dissimilar metals, along with the fabrication of surface composites to cater the mentioned problem. The objective of this study is to repair the crack produced in 6061 aluminum alloy by the reinforcement of ceramic particles, Al2O3 and B4C, to further increase the efficiency of the joint along the crack line. Weld parameters, equipment used and the processing conditions are emphasized. The mechanical testing and the characterization of the weld as well as base metal was done and compared using tensile testing, micro hardness test and microstructural analysis. X-Ray Diffraction (XRD) was performed for crystallinity and intermetallic study. The dispersion of the particles was investigated using Field Emission Scanning Electron Microscope (FESEM). The crack in the Al-6061 was effectively repaired using FSP. The reinforced samples showed improved mechanical properties as compared to non-reinforced ones.

Gli stili APA, Harvard, Vancouver, ISO e altri

15

SCHULZ, ERIC, MATTHIAS WAGNER, HOLGER SCHUBERT, WENQI ZHANG, BHARAT BALASUBRAMANIAN e LUKE N. BREWER. "Short-Pulse Resistance Spot Welding of Aluminum Alloy 6016-T4 - Part 1". Welding Journal 100, n. 01 (1 gennaio 2021): 41–51. http://dx.doi.org/10.29391/2021.100.004.

Testo completo

Abstract (sommario):

Short-pulse welding parameters for resistance spot welding (RSW) of aluminum alloy AA6016-T4 using mediumfrequency direct current (MFDC) systems were developed to reduce the heat input required for nugget formation. Optimization of current and time parameters is critical during RSW of aluminum alloys for reducing energy requirements and avoiding weld imperfections, such as solidification cracking and expulsion, while maintaining weld quality, particularly given the high electrical and thermal conductivities of the materials. The welding time and the applied current level of the current pulse were varied systematically for thin sheets (1 mm or 0.04 in.) of AA6016-T4. The quality of the welds was evaluated by pull-out testing, ultrasound testing, and metallography techniques. Simulations of the same welding processes were performed with the finite element-based SORPAS® software. The results showed short-pulse MFDC RSW can reduce the energy required for sound welds in this alloy without requiring an increase in welding current. The simulations and experiments also showed the welding process had distinct weld nugget nucleation and growth phases.

Gli stili APA, Harvard, Vancouver, ISO e altri

16

Khailov, A. N., T. N. Pen’kova, A. S. Bakunov, V. F. Muzhitskii, N. D. Presnov e V. I. Agal’tsov. "Nondestructive testing of mechanical characteristics of aluminum alloys on the basis of their electrical conductivity". Russian Journal of Nondestructive Testing 42, n. 7 (luglio 2006): 425–32. http://dx.doi.org/10.1134/s1061830906070011.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

17

Nadikudi, Bhanodaya Kiran Babu. "Effect of friction stir welding tool profiles on mechanical properties of dissimilar welded aluminum alloy plates". International Journal of Structural Integrity 12, n. 4 (8 marzo 2021): 562–68. http://dx.doi.org/10.1108/ijsi-10-2020-0097.

Testo completo

Abstract (sommario):

PurposeThe main purpose of the present work is to study the effect of tool pin profiles on mechanical properties of welded plates made with two different aluminium alloy plates.Design/methodology/approachThe welded plates were fabricated with the three different kinds of pin profiled tools such as taper cylindrical, taper threaded cylindrical and stepped cylindrical pin profiles. Tensile properties of welded plates were evaluated using tensile testing machine at room temperature. Microstructures studies were carried out using scanning electron microscope.FindingsTensile properties were improved with the use of taper threaded cylindrical pin tool in friction stir welding process when compared with taper cylindrical and stepped cylindrical pin tools. This is due to refinement of grains and mixing of plasticized material occurred with generation of sufficient heat with the taper threaded pin tool. Through these studies, it was confirmed that friction stir welding can be used to weld Al6061 and Al2014 aluminium alloy plates.Research limitations/implicationsIn the present study, the friction stir welding is performed with constant process parameters such as tool rotational speed of 900 rpm, transverse speed of 24 mm/min and tilt angle of 1°.Practical implicationsAluminium alloys are widely using in automotive and aerospace industries due to holding a high strength to weight property. These aluminium alloy blanks can be developed with friction stir welding method with better properties.Originality/valueVery limited work had been carried out on friction stir welding of aluminium alloys of Al 6061 and Al2014 with different tool pin profiles. Furthermore, this work analyzed with tensile properties of welded plates correlated with weld zone microstructures.

Gli stili APA, Harvard, Vancouver, ISO e altri

18

Petersen, DR, L. Schra e FF Groep. "The ASCOR Test: A Simple Automated Method for Stress Corrosion Testing of Aluminum Alloys". Journal of Testing and Evaluation 21, n. 1 (1993): 44. http://dx.doi.org/10.1520/jte11740j.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

19

Holroyd, N. J. Henry, Timothy L. Burnett, Benjamin C. Palmer e John J. Lewandowski. "Estimation of environment-induced crack growth rate as a function of stress intensity factors generated during slow strain rate testing of aluminum alloys". Corrosion Reviews 37, n. 5 (25 settembre 2019): 499–506. http://dx.doi.org/10.1515/corrrev-2019-0031.

Testo completo

Abstract (sommario):

AbstractIn this contribution, we introduce a simple approach to quickly estimate the environment-induced crack velocity (CV) as a function of the calculated applied stress intensity factor (K) developed during the slow strain rate testing of aluminum alloys exposed to aqueous or humid air-type environments. The CV-K behavior for a commercial aluminum-magnesium alloy, AA5083-H131, sensitized and pre-exposed to a 0.6 m NaCl solution has been estimated from slow strain rate test data. The predicted threshold K and crack velocities match recently published data for the same alloy in similarly sensitized conditions where the CV-K data were obtained using state-of-the-art fracture mechanics-based testing.

Gli stili APA, Harvard, Vancouver, ISO e altri

20

Li, Yi Tai, Wei He Shi, Bin Sui, Jing Li e Jian Min Zeng. "Study on Mechanical Properties of High Aluminum Zinc-Based Alloys with Different Al Contents Ranging from 30 wt% to 50 wt%". Advanced Materials Research 712-715 (giugno 2013): 30–33. http://dx.doi.org/10.4028/www.scientific.net/amr.712-715.30.

Testo completo

Abstract (sommario):

The mechanical properties and microstructures of zinc-based alloys with different Al-contents ranging from 30 wt% to 50 wt% were studied by means of DSC, metallography and tensile testing under different temperatures in the present work. The experimental results show that the ZA40 is of the best comprehensive properties and ZA50 better high-temperature performance among the five alloys.

Gli stili APA, Harvard, Vancouver, ISO e altri

21

Xie, Dongyue, Binqiang Wei, Wenqian Wu e Jian Wang. "Crystallographic Orientation Dependence of Mechanical Responses of FeCrAl Micropillars". Crystals 10, n. 10 (16 ottobre 2020): 943. http://dx.doi.org/10.3390/cryst10100943.

Testo completo

Abstract (sommario):

Iron-chromium-aluminum (FeCrAl) alloys are used in automobile exhaust gas purifying systems and nuclear reactors due to its superior high-temperature oxidation and excellent corrosion resistance. Single-phase FeCrAl alloys with a body centered cubic structure plastically deform through dislocation slips at room temperature. Here, we investigated the orientation dependence of mechanical responses of FeCrAl alloy through testing single-crystal and bi-crystal micropillars in a scanning electron microscopy at room temperature. Single-crystal micropillars were fabricated with specific orientations which favor the activity of single slip system or two slip systems or multiple slip systems. The strain hardening rate and flow strength increase with increasing the number of activated slip system in micropillars. Bi-crystal micropillars with respect to the continuity of slip systems across grain boundary were fabricated to study the effect of grain boundary on slip transmission. The high geometrical compatibility factor corresponds to a high flow strength and strain hardening rate. Experimental results provide insight into understanding mechanical response of FeCrAl alloy and developing the mechanisms-based constitutive laws for FeCrAl polycrystalline aggregates.

Gli stili APA, Harvard, Vancouver, ISO e altri

22

Zhang, R. Y., S. W. Yu, K. H. Zhang e F. C. Wang. "Spinnability of Semi-Continuous Casting 7A09 Aluminum Alloy". Advanced Materials Research 97-101 (marzo 2010): 361–64. http://dx.doi.org/10.4028/www.scientific.net/amr.97-101.361.

Testo completo

Abstract (sommario):

7A09 aluminum alloy is served as an important structural material in many fields. In this paper, power spinning of semi-continuous casting 7A09 aluminum alloy tube blank was carried out, and the effects of process parameters, such as spinning temperature and roller feeding ratio, on spinnability were analyzed, further the mechanical property was tested on a tensile testing machine. The results show that: at 300°C and 1.2mm/r roller feeding ratio, semi-continuous casting 7A09 aluminum alloy tube blank has good spinnability; after spun, the yield strength is increased 44%, and elongation is increased 130%.

Gli stili APA, Harvard, Vancouver, ISO e altri

23

Baran, Marta, Dominik Nowakowski, Janusz Lisiecki e Sylwester Kłysz. "Mechanical Tests Applied to Structural Health Monitoring: An Overview of Previous Experience". Fatigue of Aircraft Structures 2020, n. 12 (1 dicembre 2020): 123–35. http://dx.doi.org/10.2478/fas-2020-0012.

Testo completo

Abstract (sommario):

Abstract Laboratory for Materials Strength Testing (LMST) has been conducting accredited mechanical research for aviation from 2003. Among accredited procedures are e.g. low and high cycle fatigue tests, fracture toughness tests and fatigue crack growth rate tests. The main goal of them is obtaining materials constants and characteristics. However knowledge how to conduct these tests could be used also in other applications, for instance in the work on development of Structural Health Monitoring systems (SHM). When cracks propagate in a controlled way in laboratory conditions, it allows verifying the operation of a single sensor or a network of sensors. In this paper, an overview of mechanical tests carried out at the Laboratory for Materials Strength Testing within Air Force Institute of Technology (AFIT) work on research and development of SHM systems is presented. Specimens prepared from materials such as aluminum alloys (among other withdrawn PZL-130 Orlik TC-II aircraft) and CFRP composite were tested under different mechanical loads, i.e., cycle and impact loads. In the presented research, both constant amplitude and spectrum loads were applied.

Gli stili APA, Harvard, Vancouver, ISO e altri

24

Shi, Chang Liang, Yan Ping Niu, Yi Min Lin, Quan Hu e Xin Zhang. "Effect of Coarse-Grained Ring on Mechanical Properties and Cutting Performance of 2011 Aluminum Alloy Extruded Bar". Materials Science Forum 1035 (22 giugno 2021): 114–18. http://dx.doi.org/10.4028/www.scientific.net/msf.1035.114.

Testo completo

Abstract (sommario):

The effects of coarse-grained ring on the mechanical properties and cutting performance of 2011 aluminum alloy extruded bars were studied by metallographic microscope, scanning electron microscope, tensile testing machine and high-speed lathe. The results show that the microstructure of aluminum alloy extruded bar was composed of α-Al phase, Al7Cu2Fe phase, CuAl2 phase and SnBi eutectic phase. There was a coarse-grained ring in the aluminum alloy extruded bar. The coarse-grained ring reduced the mechanical properties and cutting performance of the aluminum alloy extruded bar. The aluminum alloy extruded bar with a diameter of 30 mm had a coarse-grained ring depth of 9 mm and lower mechanical properties, whose the tensile strength was 287.9 MPa, the elongation was 17%, the cutting performance was poor and the chips were long. The aluminum alloy extruded bar with a diameter of 40 mm had a coarse-grained ring depth of 1 mm, higher mechanical properties and better cutting performance, whose the tensile strength was 394.5 MPa, the elongation was 23.5%, the chips were fine and uniform.

Gli stili APA, Harvard, Vancouver, ISO e altri

25

Gaines, Ed, e John Banker. "Shipboard Aluminum/Steel Welded Transition Joints: Evaluations and Improvements". Journal of Ship Production 7, n. 03 (1 agosto 1991): 188–99. http://dx.doi.org/10.5957/jsp.1991.7.3.188.

Testo completo

Abstract (sommario):

Aluminum-to-steel explosion-welded transition joints are used to attach aluminum superstructures to steel hulls. Transition joint bond separation sometimes occurs during ship construction. Ingalls Shipbuilding conducted a long-term study to determine causes and corrective action for these separations. Aluminum/steel transition joints are manufactured by the explosion-bonding process and tested in accordance with MIL-J-24445. Traditional transition joints consist of alloyed aluminum bonded to mild steel with an interlayer of low-alloy aluminum. The study reviews transition joint manufacture and quality testing required by material specification, adequacy of design guidelines and production practices, and cost-effective methods for corrective action. Modifications in product design and testing, installation design and shipyard production practices can improve reliability. The most important result of this study was development of material with improved properties. This paper relates the study procedure, findings and recommendations so that transition joint separations can be avoided on future installations. This information is useful for designers and transition joint users

Gli stili APA, Harvard, Vancouver, ISO e altri

26

Liu, M. D., e J. J. Xiong. "Fatigue Crack Growth Testing and Evaluation for Aluminum Alloys at Temperatures of 25°C and −70°C". Journal of Testing and Evaluation 46, n. 4 (11 dicembre 2017): 20160592. http://dx.doi.org/10.1520/jte20160592.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

27

Kadigithala, Nagabhushan Kumar, e Vanitha C. "Effects of welding speeds on the microstructural and mechanical properties of AZ91D Mg alloy by friction stir welding". International Journal of Structural Integrity 11, n. 6 (13 marzo 2020): 769–82. http://dx.doi.org/10.1108/ijsi-12-2019-0131.

Testo completo

Abstract (sommario):

PurposeThe main purpose of the present work is to evaluate, the microstructural and mechanical properties of friction stir welded plates of AZ91D magnesium alloy with 3 mm thickness, and to determine the optimum range of welding conditions.Design/methodology/approachMicrostructure and fractographic studies were carried out using scanning electron microscopy (SEM). Vickers micro hardness test was performed to evaluate the hardness profile in the region of the weld area. The phases in the material were confirmed by X-Ray diffraction (XRD) analysis. Transverse tensile tests were conducted using universal testing machine (UTM) to examine the joint strength of the weldments at different parameters.FindingsMetallographic studies revealed that each zone shown different lineaments depending on the mechanical and thermal conditions. Significant improvement in the hardness was observed between the base material and weldments. Transverse tensile test results of weldments had shown almost similar strength that of base material regardless of welding speed. Fractographic examination indicated that the welded specimens failed due to brittle mode fracture. Through these studies it was confirmed that friction stir welding (FSW) can be used for the welding of AZ91D magnesium alloy.Research limitations/implicationsIn the present study, the welding speed varied from 25 mm/min to 75 mm/min, tilt angle varied from 1.5° to 2.5° and constant rotational speed of 500 rpm.Practical implicationsMagnesium and aluminum based alloys which are having high strength and low density, used in automotive and aerospace applications can be successfully joined using FSW technique. The fusion welding defects can be eliminated by adopting this technique.Originality/valueLimited work had been carried out on the FSW of magnesium based alloys over aluminum based alloys. Furthermore, this paper analyses the influence of welding parameters over the microstructural and mechanical properties.

Gli stili APA, Harvard, Vancouver, ISO e altri

28

Mueller, Erik, Luis Carney e Kara Mixson. "Use of Eddy Current Conductivity and Hardness Testing to Evaluate Heat Damage in Aluminum Alloys". Journal of Failure Analysis and Prevention 18, n. 1 (12 dicembre 2017): 50–54. http://dx.doi.org/10.1007/s11668-017-0380-6.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

29

Smerd, R., S. Winkler, C. Salisbury, M. Worswick, D. Lloyd e M. Finn. "High strain rate tensile testing of automotive aluminum alloy sheet". International Journal of Impact Engineering 32, n. 1-4 (dicembre 2005): 541–60. http://dx.doi.org/10.1016/j.ijimpeng.2005.04.013.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

30

Su, Mei-Ni, Ben Young e Leroy Gardner. "Testing and Design of Aluminum Alloy Cross Sections in Compression". Journal of Structural Engineering 140, n. 9 (settembre 2014): 04014047. http://dx.doi.org/10.1061/(asce)st.1943-541x.0000972.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

31

Zhu, Deju, Barzin Mobasher, S. D. Rajan e Pedro Peralta. "Characterization of Dynamic Tensile Testing Using Aluminum Alloy 6061-T6 at Intermediate Strain Rates". Journal of Engineering Mechanics 137, n. 10 (ottobre 2011): 669–79. http://dx.doi.org/10.1061/(asce)em.1943-7889.0000264.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

32

Al-Obaisi, A. M., E. A. El-Danaf, A. E. Ragab, M. S. Soliman e A. N. Alhazaa. "Statistical Model for the Mechanical Properties of Al-Cu-Mg-Ag Alloys at High Temperatures". Advances in Materials Science and Engineering 2017 (2017): 1–13. http://dx.doi.org/10.1155/2017/1691465.

Testo completo

Abstract (sommario):

Aluminum alloys for high-temperature applications have been the focus of many investigations lately. The main concern in such alloys is to maintain mechanical properties during operation at high temperatures. Grain coarsening and instability of precipitates could be the main reasons behind mechanical strength deterioration in these applications. Therefore, Al-Cu-Mg-Ag alloys were proposed for such conditions due to the high stability of Ω precipitates. Four different compositions of Al-Cu-Mg-Ag alloys, designed based on half-factorial design, were cast, homogenized, hot-rolled, and isothermally aged for different durations. The four alloys were tensile-tested at room temperature as well as at 190 and 250°C at a constant initial strain rate of 0.001 s−1, in two aging conditions, namely, underaged and peak-aged. The alloys demonstrated good mechanical properties at both aging times. However, underaged conditions displayed better thermal stability. Statistical models, based on fractional factorial design of experiments, were constructed to relate the experiments output (yield strength and ultimate tensile strength) with the studied process parameters, namely, tensile testing temperature, aging time, and copper, magnesium, and silver contents. It was shown that the copper content had a great effect on mechanical properties. Also, more than 80% of the variation of the high-temperature data was explained through the generated statistical models.

Gli stili APA, Harvard, Vancouver, ISO e altri

33

Tijani, Y., A. Heinrietz, T. Bruder e H. Hanselka. "Quantitative evaluation of fatigue life of cast aluminum alloys by non-destructive testing and parameter model". International Journal of Fatigue 57 (dicembre 2013): 73–78. http://dx.doi.org/10.1016/j.ijfatigue.2013.05.017.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

34

Kou, L. Y., W. Y. Zhao, X. Y. Tuo, G. Wang e C. R. Sun. "Effect of stress triaxiality on fracture failure of 6061 aluminium alloy". Journal of Mechanical Engineering and Sciences 14, n. 2 (23 giugno 2020): 6961–70. http://dx.doi.org/10.15282/jmes.14.2.2020.33.0545.

Testo completo

Abstract (sommario):

The effect of stress triaxiality on mechanical properties of 6061 aluminium alloy extruded profiles with different specimens was studied. Macroscopic mechanical property of the various specimen was got through universal testing machine. At the same time, stress triaxiality of different specimens was obtained using the method of finite element simulation. And then the fracture strain of each specimen was outputted by DIC. Fracture modes of 6061 aluminium alloy with different stress triaxiality were studied by SEM. The results show that taking tensile samples as comparison, the cross-sectional area of some notched specimens decreases and the peak load increases. Among them, the minimum cross-sectional area of the R5 central hole specimen is 20% smaller than that of the tensile sample, and the peak load is 28% larger. The fracture strain of the alloy increased with the decrease of stress triaxiality. For the same notch specimens, along the path direction, stress triaxiality of R5 notch specimens, R5 Center-hole specimens and R20 Arc notched specimens increased 47%, 17.8%, 25% respectively. According to the analysis of fracture morphology, the main fracture of 6061 aluminium alloy was ductile fracture. When the stress triaxiality is large, the dimples are small and sparsely distributed, and when the stress triaxiality is small, the dimple is large and evenly distributed. Finally, the Johnson-Cook model material parameters of 6061 aluminum alloy are fitted based on the tensile test results of different shapes of specimens, which can accurately simulate the elastic-plastic deformation and fracture instability of 6061 aluminum alloy under different stress states.

Gli stili APA, Harvard, Vancouver, ISO e altri

35

Papadopoulos, Michael, e Spiros Pantelakis. "Fatigue testing of 2198 T8 FSW aluminum alloy with and without LoP defect". International Journal of Structural Integrity 8, n. 4 (14 agosto 2017): 496–504. http://dx.doi.org/10.1108/ijsi-04-2016-0015.

Testo completo

Abstract (sommario):

Purpose The Lack of Penetration (LoP) defect is one of the flaws that can be generated during the friction stir welding (FSW) process. Depending on the size, the depth and the severity of the LoP defect, it is possible that it is hardly detectable by optical inspection or other NDT methods. Whether detectable or not, this defect may lead to a significant degradation of the fatigue properties of the welded material, as the improperly welded zone can act as a fracture initiation site. The paper aims to discuss these issues. Design/methodology/approach In this experimental investigation, an attempt is made to assess and compare the fatigue behavior of FSW aluminum joints with and without the LoP defect. Findings It was found that the LoP defect affects the fatigue behavior of the welded material at high stress levels whereas the effect diminishes with decreasing stress levels. Originality/value Depending on the design stress levels, the LoP defect may dominate fracture and thus, the welding parameters should be carefully selected so as to avoid such defect.

Gli stili APA, Harvard, Vancouver, ISO e altri

36

Zheng, Jing Wu, Zi He, Wei Cai, Si Yuan Chen, Liang Qiao, Yao Ying e Li Qiang Jiang. "Low Resistivity Aluminium Alloy of High Tensile Strength and Elongation". Advanced Materials Research 676 (marzo 2013): 3–7. http://dx.doi.org/10.4028/www.scientific.net/amr.676.3.

Testo completo

Abstract (sommario):

Through testing the mechanical properties and electrical property, the conductive aluminum alloy with high strength and elongation was obtained by adjusting the content of Fe, B and misch metal elements constantly, and the influence mechanism of the add elements was discussed by observing microstructure morphology of the aluminum alloy. The results indicated that the addition of Fe could effectively improve the tensile strength of commercial aluminum, while the addition of misch metal could change the existence form of Fe, thus to compensating for the decrease of elongation because of the addition of Fe. On the other hand, the addition of appropriate B could remove the harmful impurity elements of the aluminum alloy and refining the grain, so as to reduce the resistivity of the aluminum alloy with adding iron and rare earth elements. Finally, the optimum was obtained which was the composition of 99.18%Al-0.75%Fe-0.05%Re-0.02%B, the tensile strength was 103MPa, the elongation was 30.98% and the resistivity was 2.737×10-8Ω•m.

Gli stili APA, Harvard, Vancouver, ISO e altri

37

Nouri, A., X. B. Chen, Peter D. Hodgson e Cui E. Wen. "Preparation and Characterisation of New Titanium Based Alloys for Orthopaedic and Dental Applications". Advanced Materials Research 15-17 (febbraio 2006): 71–76. http://dx.doi.org/10.4028/www.scientific.net/amr.15-17.71.

Testo completo

Abstract (sommario):

Various types of titanium alloys with high strength and low elastic modulus and, at the same time, vanadium and aluminium free have been developed as surgical biomaterials in recent years. Moreover, porous metals are promising hard tissue implants in orthopaedic and dentistry, where they mimic the porous structure and the low elastic modulus of natural bone. In the present study, new biocompatible Ti-based alloy foams with approximate relative densities of 0.4, in which Sn and Nb were added as alloying metals, were synthesised through powder metallurgy method. The new alloys were prepared by mechanical alloying and subsequently sintered at high temperature using a vacuum furnace. The characteristics and the processability of the ball milled powders and the new porous titanium-based alloys were characterised by X-ray diffraction, optical microscopy and scanning electron microscopy .The mechanical properties of the new titanium alloys were examined by Vickers microhardness measurements and compression testing.

Gli stili APA, Harvard, Vancouver, ISO e altri

38

Banabic, D., M. Vulcan e K. Siegert. "Bulge Testing under Constant and Variable Strain Rates of Superplastic Aluminium Alloys". CIRP Annals 54, n. 1 (2005): 205–8. http://dx.doi.org/10.1016/s0007-8506(07)60084-5.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

39

Rossel, Moritz, Max Böhnke, Christian Bielak, Mathias Bobbert e Gerson Meschut. "Development of a Method for the Identification of Friction Coefficients in Sheet Metal Materials for the Numerical Simulation of Clinching Processes". Key Engineering Materials 883 (aprile 2021): 81–88. http://dx.doi.org/10.4028/www.scientific.net/kem.883.81.

Testo completo

Abstract (sommario):

In order to reduce the fuel consumption and consequently the greenhouse emissions, the automotive industry is implementing lightweight constructions in the body in white production. As a result, the use of aluminum alloys is continuously increasing. Due to poor weldability of aluminum in combination with other materials, mechanical joining technologies like clinching are increasingly used. In order to predict relevant characteristics of clinched joints and to ensure the reliability of the process, it is simulated numerically during product development processes. In this regard the predictive accuracy of the simulated process highly depends on the implemented friction model. In particular, the frictional behavior between the sheet metals affects the geometrical formation of the clinched joint significantly. This paper presents a testing method, which enables to determine the frictional coefficients between sheet metal materials for the simulation of clinching processes. For this purpose, the correlation of interface pressure and the relative velocity between aluminum sheets in clinching processes is investigated using numerical simulation. Furthermore, the developed testing method focuses on the specimen geometry as well as the reproduction of the occurring friction conditions between two sheet metal materials in clinching processes. Based on a methodical approach the test setup is explained and the functionality of the method is proven by experimental tests using sheet metal material EN AW6014.

Gli stili APA, Harvard, Vancouver, ISO e altri

40

Khandaker, Morshed, Abdellah Ait Moussa, Desmond Nuyebga Sama, Fereshteh Safavinia, Susmita Hazra, Onur Can Kalay, Fatih Karpat, Erik Clary e Amgad Haleem. "Laser-Induced Microgrooves Improve the Mechanical Responses of Cemented Implant Systems". Micromachines 11, n. 5 (29 aprile 2020): 466. http://dx.doi.org/10.3390/mi11050466.

Testo completo

Abstract (sommario):

The impact of a laser-induced microgroove (LIM) architecture on mechanical responses of two cemented implant systems was evaluated. One system consisted of two aluminum alloy rods bonded end-to-end by polymethylmethacrylate cement. The second system consisted of a custom-made, aluminum tibial tray (TT) cemented in an artificial canine tibia. Control specimens for each system were polished smooth at the cement interface. For LIM samples in the rod system, microgrooves were engraved (100 µm depth, 200 µm width, 500 µm spacing) on the apposing surface of one of the two rods. For TT system testing, LIM engraving (100 µm spacing) was confined to the underside and keel of the tray. Morphological analysis of processed implant surfaces revealed success in laser microgrooving procedures. For cemented rods tested under static tension, load to failure was greater for LIM samples (279.0 ± 14.9 N vs. 126.5 ± 4.5 N). Neither non-grooved nor grooved TT samples failed under cyclic compression testing (100,000 cycles at 1 Hz). Compared with control specimens, LIM TT constructs exhibited higher load to failure under static compression and higher strain at the bone interface under cyclic compression. Laser-induced microgrooving has the potential to improve the performance of cemented orthopedic implants.

Gli stili APA, Harvard, Vancouver, ISO e altri

41

Mugendiran, V., A. Gnanavelbabu e R. Ramadoss. "Tensile Behaviour of Al5052 Alloy Sheets Annealed at Different Temperatures". Advanced Materials Research 845 (dicembre 2013): 431–35. http://dx.doi.org/10.4028/www.scientific.net/amr.845.431.

Testo completo

Abstract (sommario):

With recent development in automotive industries, aluminium alloys have great demand in sheet metal fabrication industries. Sheet metal forming at slightly elevated temperatures is more acceptable in forming operations. The mechanical properties such as yield strength, ultimate tensile strength and percentage of elongation are very influential in determining the formability of sheet metals in various applications. In this paper, tensile property of Al5052 alloy is investigated at constant strain rate under different annealing conditions from room to 350°C. Servo controlled universal testing machine was used for tensile testing. The results of tensile testing indicate that the tensile properties including yield strength, ultimate tensile strength decreases and elongation percentage increases with the increase in annealing temperature. The analysis shows that the formability parameters, strain hardening index and strength coefficient increase with increase in annealing temperatures.

Gli stili APA, Harvard, Vancouver, ISO e altri

42

Yu, Jin, Yin Zhuo Huang, Bo Wen Wu e Hou Xian Zhou. "Structure and Performance of Fe-Al Alloy Layer for Twin Wire Surfacing on the Steel Substrate". Advanced Materials Research 658 (gennaio 2013): 158–64. http://dx.doi.org/10.4028/www.scientific.net/amr.658.158.

Testo completo

Abstract (sommario):

Surfacing of Fe-Al alloy layer is achieved on the surface of Q235 steel plate by using the twin wire consisting of one aluminum welding wire and one steel welding wire in the shielding of pure argon. When the ER1100 aluminum welding wire of Φ1.6mm and ER50-6 steel welding wire of Φ1.2mm are selected as the master wire and slave wire respectively, with preheating and interlayer temperature reaching 350°C by controlling filling volume of aluminum and steel , the Fe-Al alloy layer featured by well-formed welding line is thus gained with no macroscopic defect. As the mechanical performance testing shows, the shear strength of surface combining surfacing layer and steel substrate is higher than 270MPa. The rupture position is located in surfacing layer and it turns out to be brittle fracture; the micro-hardness of surfacing layer ranges from 320HV to 420HV. Abrasion resistance testing indicates that abrasion resistance of surfacing layer is better than that of base material. According to micro-structure observation, the welding line is a coarsening columnar structure with a great deal of precipitated phase. According to EDAX, the aluminum content of precipitated phase in surfacing layer ranges from 24% to 32% (at), and the steel content ranging from 76% to 68% (at) - it is thus considered a Fe3Al structure through XRD.

Gli stili APA, Harvard, Vancouver, ISO e altri

43

Hoskin, G. A., J. W. Provan e J. E. Gruzleski. "The in-situ fatigue testing of a cast aluminum-silicon alloy". Theoretical and Applied Fracture Mechanics 10, n. 1 (agosto 1988): 27–41. http://dx.doi.org/10.1016/0167-8442(88)90054-7.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

44

Zhang, Suhong, Alan Frederick, Yiyu Wang, Mike Eller, Paul McGinn, Anming Hu e Zhili Feng. "Microstructure Evolution and Mechanical Property Characterization of 6063 Aluminum Alloy Tubes Processed with Friction Stir Back Extrusion". JOM 71, n. 12 (29 ottobre 2019): 4436–44. http://dx.doi.org/10.1007/s11837-019-03852-7.

Testo completo

Abstract (sommario):

Abstract Friction stir back extrusion (FSBE) is a technique for lightweight metal extrusion. The frictional heat and severe plastic deformation of the process generate an equiaxed refined grain structure because of dynamic recrystallization. Previous studies proved that the fabrication of tube and wire structures is feasible. In this work, hollow cylindrical billets of 6063-T6 aluminum alloy were used as starting material. A relatively low extrusion ratio allows for a temperature and deformation gradient through the tube wall thickness to elucidate the effect of heat and temperature on the microstructure evolution during FSBE. The force and temperature were recorded during the processes. The microstructures of the extruded tubes were characterized using an optical microscope, energy-dispersive x-ray spectroscopy, electron backscatter diffraction, and hardness testing. The process reduced the grain size from 58.2 μm to 20.6 μm at the inner wall. The microhardness of the alloy was reduced from 100 to 60–75 HV because of the process thermal cycle.

Gli stili APA, Harvard, Vancouver, ISO e altri

45

Krupp, Ulrich, Thomas Hipke e Srecko Nesic. "Structural Loading of Cellular Metals: Damage Mechanisms and Standardization Concepts". Materials Science Forum 933 (ottobre 2018): 220–25. http://dx.doi.org/10.4028/www.scientific.net/msf.933.220.

Testo completo

Abstract (sommario):

Structural loading of cellular metals is strongly affected by brittle fracture of cell struts and walls that exhibit tensile loads, e.g., during fatigue loading. The present paper summarizes results of compression, tension and cyclic loading experiments on various closed-cell metal foams and metal foam sandwiches (Alulight, Alporas, Foamtech, AFS) using various mechanical testing systems. The results were correlated with a thorough analysis of the cellular mesostructure and the cell strut/wall microstructure by means of scanning electron microscopy revealing defects, such as casting porosity and large Si precipitates in the Al-Si eutectic of aluminum cast alloy. The results of the work served for the definition of testing standards for compression testing (ISO 13314) and tensile testing (DIN 50099), which are outlined in the paper. Such standards and design guidelines are crucial for a successful implementation of cellular metals in innovative products in mechanical, automotive and energy engineering as well as in bioengineering.

Gli stili APA, Harvard, Vancouver, ISO e altri

46

Di, Chang Chun, Kai Bo Cui, Jun Qi Qin e Da Lin Wu. "Parameters Identification of Johnson-Cook Constitutive Equation for Aluminum Brass". Advanced Materials Research 887-888 (febbraio 2014): 1032–35. http://dx.doi.org/10.4028/www.scientific.net/amr.887-888.1032.

Testo completo

Abstract (sommario):

Aluminum brass HAL66-6-3-2 is abrasion-resistant alloy with high strength, hardness and wear resistance, corrosion resistance is also well, commonly used in the field of marine and ordnance industry. The quasi static and dynamic mechanical properties were tested through the use of electronic universal testing machine and Split Hopkinson Tension Bar (SHTB). Meanwhile, the material stress-strain curve at different temperatures and different strain rates is also obtained. Based on Johnson-Cook constitutive model, using the method of least squares fitting the experimental data to determine the model parameters, fitting and experimental results agree well.

Gli stili APA, Harvard, Vancouver, ISO e altri

47

Wasekar, Milind K., e Mohan P. Khond. "Effect of addition of different reinforcements on the microstructure and mechanical characterization of the Al-Flyash composites". Frattura ed Integrità Strutturale 15, n. 56 (28 marzo 2021): 217–28. http://dx.doi.org/10.3221/igf-esis.56.18.

Testo completo

Abstract (sommario):

The aim of this work is to investigate the influence of the addition of silicon carbide and molybdenum disulfide on the microstructure and the tensile strength of the Al-Flyash hybrid composites prepared using the stir casting technique. The composite with aluminum 6061 alloy as the matrix and flyash as the reinforcement, with different weight fractions, is investigated to study its microstructure and the tensile strength. The same has been compared with the hybrid composites with Aluminum-Flyash/SiC and Aluminum-Flyash/MoS2 for different weight fractions of the reinforcements. The tensile tests were conducted as per ASTM standard testing procedures at room temperature. From the results it is identified that tensile strength of the Al6061-Flyash composite is lesser than the Al6061-Flyash/SiC and Al6061-Flyash/MoS2 hybrid composites. It is also observed that increment in the composition of the SiC and MoS2 causes the increment in the tensile strength of the hybrid composite. This increment in the tensile strength is due to good interface bonding and uniform distribution of the reinforcements in the composite.

Gli stili APA, Harvard, Vancouver, ISO e altri

48

Othman, R., e G. Gary. "Testing Aluminum Alloy from Quasi-static to Dynamic Strain-rates with a Modified Split Hopkinson Bar Method". Experimental Mechanics 47, n. 2 (3 febbraio 2007): 295–99. http://dx.doi.org/10.1007/s11340-006-9023-7.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

49

TAKAHASHI, Akihiro, Toshiro KOBAYASHI, Hiroyuki TODA e Tohru MIZUTANI. "Effect of testing temperature from cryogenic to high temperatures on dynamic fracture properties in 5083 aluminum alloy." Journal of Japan Institute of Light Metals 50, n. 8 (2000): 386–91. http://dx.doi.org/10.2464/jilm.50.386.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

50

Dharmadhikari, Susheel, Chandrachur Bhattacharya, Asok Ray e Amrita Basak. "A Data-Driven Framework for Early-Stage Fatigue Damage Detection in Aluminum Alloys Using Ultrasonic Sensors". Machines 9, n. 10 (25 settembre 2021): 211. http://dx.doi.org/10.3390/machines9100211.

Testo completo

Abstract (sommario):

The paper presents a coupled machine learning and pattern recognition algorithm to enable early-stage fatigue damage detection in aerospace-grade aluminum alloys. U- and V-notched Al7075-T6 specimens are instrumented with a pair of ultrasonic sensors and, thereafter, tested on an MTS apparatus integrated with a confocal microscope and a digital microscope. The confocal microscope is focused on the notch root of the specimens, whereas the digital microscope is focused on the side of the notch. Two features, viz., the crack opening displacement (COD) and the crack length, are extracted during the tests in addition to the ultrasonic signal data. These signal data are analyzed using a machine learning framework that is built upon a symbolic time-series algorithm. This framework is interrogated for crack detection in the crack coalescence (CC) regime defined by COD of ~3 μm and detected through the confocal microscope. Additionally, the framework is probed in the crack propagation (CP) regime characterized by a crack length of ~0.2 mm and detected via the digital microscope. For the CC regime, training accuracies of 79.82% and 81.94% are achieved, whereas testing accuracies of 68.18% and 74.12% are observed for the U- and V-notched specimens, respectively. For the CP regime, overall training accuracies of 88.3% and 91.85% are observed, and accordingly, testing accuracies of 81.94% and 85.62% are obtained for the U- and V-notched specimens, respectively. The results show that a combined machine learning and pattern recognition algorithm enables robust and reliable fatigue damage detection in aerospace structural components.

Gli stili APA, Harvard, Vancouver, ISO e altri

Articoli di riviste sul tema "Aluminum alloys. Mechanical engineering. Testing"

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili