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1
Pemberton, W. Patrick. "Predictive relationships in friction stir processing of nickel-aluminum bronze". Thesis, Monterey, Calif. : Naval Postgraduate School, 2005. http://handle.dtic.mil/100.2/ADA441369.
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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, September 2005.Thesis Advisor(s): Terry R. McNelley. "September 2005." Includes bibliographical references (p. 45-47). Also available in print.
2
Fuller, Michael D. "Friction stir processing and fusion welding in nickel aluminum propeller bronze". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2006. http://library.nps.navy.mil/uhtbin/hyperion/06Mar%5FFuller.pdf.
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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, March 2006.Thesis Advisor(s): Terry R. McNelley. "March 2006." Includes bibliographical references (p. 69-70). Also available in print.
3
Jamison, Jay Dee. "Modeling of thermal and mechanical effects during friction stir processing of nickel-aluminum bronze". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Sep%5FJamison.pdf.
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Williams, Robert A. "A microstructural and mechanical property correlation of friction stir processed nickel aluminum bronze". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Sep%5FWilliams%5FR.pdf.
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Rosemark, Brian P. "Friction stir processing parameters and property distributions in cast nickel aluminum bronze". Thesis, Monterey, Calif. : Naval Postgraduate School, 2006. http://bosun.nps.edu/uhtbin/hyperion.exe/06Dec%5FRosemark.pdf.
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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2006.Thesis Advisor(s): Terry R. McNelley, Srinivasan Swaminathan. "December 2006." Includes bibliographical references (p. 49-50). Also available in print.
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Kennerknecht, Tobias [Verfasser]. "Fatigue of Micro Molded Materials - Aluminum Bronze and Yttria Stabilized Zirconia / Tobias Kennerknecht". Karlsruhe : KIT Scientific Publishing, 2014. http://www.ksp.kit.edu.
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Murray, David L. "Friction stir processing of nickel aluminum propeller bronze in comparison to fusion welds". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Jun%5FMurray.pdf.
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Pierce, Frank Allen. "The isothermal deformation of nickel aluminum bronze in relation to friction stir processing". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://handle.dtic.mil/100.2/ADA430658.
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Thesis (M.S. in Mechanical Engineering) Naval Postgreaduate School, June 2004.Thesis Advisor (s): Terry R. McNelley. "June 2004." Includes bibliographic references (p. 53-54). Also available in print.
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Nelson, Elizabeth A. "Microstructural effects of multiple passes during friction stir processing of nickel aluminum bronze". Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Dec/09Dec%5FNelson.pdf.
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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2009.Thesis Advisor: McNelley, Terry R. Second Reader: Menon, Sarath. "December 2009." Description based on title screen as viewed on January 28, 2010. Author(s) subject terms: friction stir processing, nickel aluminum bronze, propellers, microstructural properties, grain refinement, volume fraction-temperature relationship. Includes bibliographical references (p. 45-46). Also available in print.
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Cuevas, Assunta Mariela. "Microstructure characterization of friction-stir processed nickel-aluminum bronze through orientation imaging microscopy". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02sep%5FCuevas.
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Faires, Kenneth Brent. "Characterization of microstructure and microtexture in longitudinal sections from friction stir processed nickel-aluminum bronze". Thesis, Monterey, Calif. : Naval Postgraduate School, 2003. http://bosun.nps.edu/uhtbin/hyperion.exe/03Jun%5FFaires.pdf.
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LeGrand, Peggy S. "Electrochemical studies of passive film formation and corrosion of friction stir processed nickel aluminum bronze". Thesis, Monterey, California. Naval Postgraduate School, 2011. http://hdl.handle.net/10945/5716.
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Approved for public release; distribution is unlimited.The Navy currently uses Nickel-Aluminum Bronze (NAB) for its propellers. Friction stir processing (FSP) is a proposed method of improving the mechanical properties of NAB, and it is believed to improve the corrosion-resistive properties of NAB. This thesis used multiple techniques to compare the corrosion resistance of as-cast NAB with FSP NAB. Passive films were grown on the as-cast (AC) and FSP samples and modeled in order to relate the impedance data to changes in phase and microstructure resulting from FSP of NAB. Impedance modeling provides a way of measuring the passive film that forms on a metal and protects it from corrosion. In addition, cyclic polarization data was taken in order to study the stability of the films over a range of potentials. This data was then compared with SEM images to link the changes in the passive films with the changes in microstructure that occurred due to FSP.
13
Nabach, William A. "The effects of isothermal deformation and annealing on the microstructure of nickel-aluminum-bronze propeller material". Thesis, Monterey, Calif. : Naval Postgraduate School, 2003. http://bosun.nps.edu/uhtbin/hyperion.exe/03Jun%5FNabach.pdf.
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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, Terry R. McNelley.Thesis Advisor(s): Terry R. McNelley. "June 2003." Includes bibliographical references (p. 41-43). Also available in print.
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Silveira, Fabricio Dreher. "Sinterização de bronze ao alumínio seguido de endurecimento por precipitação através de envelhecimento artificial". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/17624.
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O experimento teve como objetivo o desenvolvimento de uma bucha de bronze ao alumínio de alta dureza através do processo de metalurgia do pó e endurecimento por precipitação. Iniciou-se pela definição da liga de bronze equivalente que atingiria os resultados obtidos pelo processo de fundição, ou seja, dureza final acima de 190 HB. Foram elaboradas ligas por metalurgia do pó com cobre como base e alumínio, sendo que a utilizada no processo de fundição não apresentou bons resultados na adaptação para a sinterização. Foram realizados ensaios de compactação visando a maior densidade à verde possível para as respectivas ligas. A sinterização das peças foi feita à temperatura de 885ºC em atmosfera de nitrogênio e hidrogênio até a obtenção de peças com maior resistência e menor variação dimensional. Um fator importante observado foi que o acréscimo de lubrificante na mistura prejudicou a sinterização das peças, resultando em peças com baixa resistência mecânica. Dentre as ligas de bronze estudadas, a que apresentou melhor resistência mecânica e menor variação dimensional foi a liga 81Cu - 11Al - 4Fe - 4Ni. Após a sinterização, realizou-se de ensaios de solubilização com temperaturas próximas do ponto de fusão da liga e sem atmosfera. Verificou-se que houve um crescimento máximo da dureza para a temperatura de 670 ºC, havendo decréscimo após esta temperatura. Posteriormente, as peças que sofreram maior endurecimento resultante da solubilização foram submetidas à precipitação por envelhecimento artificial. Os resultados obtidos após o envelhecimento comprovaram que houve a formação dos precipitados endurecedores e o tratamento térmico do bronze ao alumínio atingiu resultados satisfatórios em relação aos parâmetros especificados. Foram obtidas durezas acima de 150 HB.The experiment had the development of the aluminum bronze bush with high hardness by the metal powder process and precipitation hardening as target. The development was begun by the definition of the bronze alloy which would reach the results of the casting process, hardness up to 190 HB. Different alloys were prepared by powder metallurgy, and the alloy used in the casting process did not have success in adapting to the sintering. The compaction tests were carried out seeking the highest green density for the respective alloys. The sintering of the parts was done at 885ºC and nitrogen/hydrogen atmosphere to obtain the product with greater resistance and less dimensional variation. An important factor observed was that the addition of lubricant damaged the sintering of the parts, resulting in low mechanical strength. Among the bronze alloys studied, the 81Cu - 11Al - 4Fe - 4Ni alloy was chosen by having the best mechanical strength and less dimensional change. After sintering, the solution heat treatment was performed at temperatures near of the alloy’s melting point and no atmosphere. It was found that there was a maximum increase of the hardness at 670ºC, decreasing after this range. Subsequently, the samples which suffered further hardening results from the solution heat treatment were submitted to precipitation heat treatment. The results showed that after the precipitation heat treatment the hardening precipitates were created and the heat treatment of aluminum bronze reached satisfactory results for the specified parameters. Hardness over 150 HB were obtained.
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Walton, Charles Frederick. "Microtextural characterization of shear textures in the thermo-mechanically affected zone of friction stir processed nickel aluminum bronze". Thesis, Monterey, Calif. : Naval Postgraduate School, 2003. http://handle.dtic.mil/100.2/ADA421876.
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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, June 2003.Thesis Advisor(s): McNelley, Terry R. "June 2003." Description based on title screen as viewed on December 17, 2007. Includes bibliographical references (p. 53-55). Also available in print.
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Taylor, Ryan Chandler. "Effect of a Simulated Butterfly Valve on the Erosion-Corrosion Rate of Nickel Aluminum Bronze Alloys in Highly Turbulent Seawater". Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/83818.
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Nickel aluminum bronze (NAB) alloys are used in naval and maritime applications for their excellent corrosion resistance under the influence of seawater. One application involves the use of a NAB butterfly valve within a NAB fluid line to control fluid flow of seawater. Due to the chaotic environment, the corrosion rate of the NAB tubing downstream from the valve increases significantly. The disc angle at which the valve alters fluid flow causes an increase in the fluid velocity and an increase in the turbulence produced on the downstream side of the valve. These fluid conditions contribute to the increase in the corrosion rate of the NAB piping downstream from the valve. This thesis aims to characterize how the change in the disc angle of the butterfly valve causes a change in the erosion-corrosion rate of NAB downstream from the valve. A butterfly valve is simulated using orifice plates of varying diameters to mimic flow conditions at different disc angles. An orifice plate is a simple device with a hole in its center that is designed to restrict fluid flow across a fluid line. Under the same hydrodynamic conditions, the orifice produces nearly the exact same flow coefficients as the valve. At a volumetric flowrate of 0.00757 m^3/s a total of eight locations found along the liquid/metal interface produced pitting sites. The average passivation layer thickness is also measured.Master of Science
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Vazquez, Brian K. "The effects of isothermal deformation and annealing on the microstructure of nickel-aluminum-bronze in relation to the friction stir process". Thesis, Monterey, Calif. : Naval Postgraduate School, 2003. http://edocs.nps.edu/npspubs/scholarly/theses/2003/Dec/03Dec%5FVazquez.pdf.
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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2003.Thesis Advisor(s): McNelley, Terry R. "September 2008." Description based on title screen as viewed on January 21, 2009. Includes bibliographical references (p. 57-59). Also available in print.
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Phoplonker, M. A. "Stable crack growth in an aluminium-silicon bronze alloy". Thesis, University of Portsmouth, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378074.
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Shi, Z. "Electron beam surface engineering of aluminium bronzes". Thesis, University of Birmingham, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526761.
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Surface melting and alloying of commercial complex aluminium bronze CA104 has been carried out using an electron beam. In addition, other aluminium bronzes - Ampco 18, Ampco 25, CMA1 and AB2 have also been surface melted. The structural changes have been studied using optical microscopy, scanning and transmission electron microscopy, energy dispersive X-ray analysis and X-ray diffraction analysis. The hardening response to the treatments and the hardening mechanisms have been investigated. Tempering of the surface melted CA104 has also been carried out systematically to investigate the responses of the structure and hardness to subsequent heat treatment. The wear behaviour of the materials has been studied in both dry and lubricated rolling-sliding contact against hardened En19 steel and under two-body abrasive conditions against silicon carbide grinding papers. The electrochemical corrosion properties in simulated cooling water and 3.5% NaCI solution have been studied using AC impedance and DC polarisation techniques. Experimental results show that the surface layers have been transformed to martensitea fter surfacem elting due to rapid solidification and fast subsequenct ooling. The martensite in the surface melted CA104 has a 3R structure with globular precipitates dispersed in it, which are based on (Ni, Fe)A1 with a B2 structure. On subsequent tempering treatment, these precipitates grow steadily with increasing temperature and time and the martensite gradually transforms to copper-based solid solution. The hardness has been increased by surface melting as a result of the martensitic transformation and precipitation hardening. During tempering, further precipitation hardening occurs and the hardness shows a peak plotted against temperature. Surface alloying with aluminium can increase the hardness beyond that achievable by surface melting. The tungsten carbide retained after surface alloying further strengthens the alloy. The wear rate and the friction coefficient in both the dry and lubricated rolling sliding wear have been reduced by surface melting. In the dry wear test, adhesive and delamination wear are the main wear mechanisms while it is abrasive wear that dominates the lubricated wear. The abrasion resistance against silicon carbide has been increased by both surface melting and alloying, with surface alloying much more effective. The best abrasionr esistanceis obtainedf rom the material alloyed with WC particles. The results also show that the electrochemical corrosion properties are improved by surfacem elting in both electrolytesu sed. The charget ransfer resistanceis increaseda nd the corrosion current is reduced. In the simulated cooling water, the corrosion of the materials during anodic polarisation follows three steps: the formation of cuprous oxide layer on the surface; the damage and destruction of the oxide layer; the pitting and the formation of the main corrosion product, CuCl.
20
Tan, KengSoong. "Electrochemical analysis of the erosion corrosion of HVOF aluminium bronze coatings". Thesis, University of Southampton, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274707.
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Barik, Rakesh Chandra. "Environmental factors affecting the marine corrosion performance of nickel aluminium bronze". Thesis, University of Southampton, 2006. https://eprints.soton.ac.uk/64792/.
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Nickel-aluminium bronze (NAB) alloys are extensively used in seawater environments because they have good castability, toughness and erosion-corrosion performance. However, NAB alloys may encounter corrosion related problems under in-service conditions, i.e. different local environments, leading to variability in corrosion performance worldwide. Importantly, NAB alloys have complex microstructures consisting of up to 6 different phases and as a consequence they are susceptible to selective phase corrosion. The current study has primarily concentrated on the corrosion performance of cast NAB, both uncoupled and galvanically coupled, in a marine environment, namely the natural seawater at the National Oceanography Centre Southampton. With particular emphasis given to the galvanic compatibility of NAB (naval specification NES 747 Part 2), the seasonality of environmental factors such as biofouling, plus an in-depth laboratory investigation was made into the erosion-corrosion performance of cast NAB using a test slurry containing 3.5% NaCl solution and sand. A study of the corrosion performance of uncoupled NAB revealed that initially corrosion was confined mainly to the eutectoid regions with slight attack of the copper-rich -phase within the +III eutectoid. However, for prolonged exposures an adherent corrosion film formed as corrosion of the copper-rich -phase penetrated further into the NAB microstructure leaving the unattacked -phases to create an adherent skeletal lattice primarily due to the continuous nature of the III-phase. In addition, prolonged exposures resulted in selective phase corrosion which was predominately associated with an attack of the III–phase, which may also develop into pit initiation involving the formation of solid CuCl in an otherwise protective oxide film. The galvanically coupled NAB, with either itself, a wrought high strength copper-nickel alloy or a commercially pure titanium (Grade 2) showed accelerated galvanic corrosion within the first year of exposure to natural seawater which diminished in the following years. This behaviour coincided with the seasonal biofilm activity and increased likelihood of biofilm formation and kinetics. The role of bacterial metabolites/enzymes in the biofilm has been associated with an initial modification of the cathodic oxygen reduction kinetics, thus increasing the corrosion activity during the first biofilm season after exposure. Mass transfer kinetics for the anodic and cathodic reactions, as a function of flow rate, were studied in a wall-jet electrode for freshly polished pure copper and NAB. The diffusion coefficient of oxygen during cathodic reduction increases with increasing concentration oxygen. The cathodic reaction is the rate controlling step in the corrosion process. The high mass transfer coefficient for the oxygen has been attributed to the higher turbulence intensity within the wall-jet cell compared with either rotating disc or cylinder electrodes. Under flow corrosion, erosion and erosion-corrosion conditions (jet impingement) the cast NAB demonstrated superior performance than HVOF NAB coatings. The flow corrosion rates for cast NAB and HVOF NAB coating was found to be 0.5-0.8 and 0.8-1.5 mm y-1, respectively. Compared with the cast NAB, the porous nature of the HVOF coating and the presence of coating impurities undermined the corrosion performance. Likewise, the erosion behaviour of HVOF NAB coating was due to the high flaw density and splat boundaries, which act as crack initiators. The high kinetic energy exponent in HVOF NAB coating suggested a combination of both ductile and brittle erosion mechanisms possibly due to the porosity. In contrast, the cast NAB resulted in an energy exponent close to unity consistent with ductile materials. A SEM study revealed the cast NAB had undergone plastic deformation at the maximum erosion depth while microcutting was seen outside the centre of erosion scar. The synergistic effect based on the gravimetric, electrochemical and surface hardness measurements are also presented. The negative synergy in general infer to the good properties of the material.
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Neodo, Stefano. "Electrochemical monitoring of nickel-aluminium bronze crevice corrosion solutions using boron-doped diamond electrode". Thesis, University of Southampton, 2013. https://eprints.soton.ac.uk/355881/.
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This study has demonstrated the capability of electrochemically assessing the metal–ion concentrations generated from the localised corrosion of nickel–aluminium bronzes (NAB). Prior to investigating NAB crevice corrosion, its electrochemical properties were studied at different pHs and chloride concentrations. At solution pHs higher than 4 NAB exhibited a corrosion behaviour similar to that of unalloyed copper and its oxidation was controlled by the dissolution of the copper–rich α–phase. However, as the pH was decreased below 4 the corrosion mechanism changed and the other κ–phases rich in aluminium, iron and nickel underwent preferential oxidation. The NAB corrosion performance was also investigated in the presence of benzotriazole (inhibitor) by using potentiodynamic polarisation. The excellent corrosion properties showed by NAB when exposed to neutral benzotriazole solution made the studied inhibitor a promising candidate for limiting crevice corrosion. With knowledge of the NAB corrosion behaviour and the relatively high copper– and nickel–ion extents present within the crevice corrosion solutions, a study related to their electrochemical behaviour and detection was undertaken using a boron–doped diamond (BDD) electrode at different pHs and chloride levels in order to establish viable electrochemical protocols for effectively assess these concentrations. Before investigating the copper and nickel electrochemical behaviours on BDD electrode, the diamond substrate was studied using a number of different techniques such as potentiodynamic polarisation, cyclic voltammetry and electrochemical impedance spectroscopy. Results highlighted its excellent performance having a wide potential window (ca. 3 V) and a low capacitive current (20 μF cm–2 in 0.5 M H2SO4) available for electroanalysis purposes. Finally, the NAB crevice corrosion was monitored using a BDD microelectrode array. The employed setup created an artificial crevice and accommodated the BDD microelectrode array for in situ and a real–time monitoring. The electrochemical response showed the only presence of copper(I) during the investigated time, whose concentration increased within the first two hundred hours to a level of ca. 0.4 mM and then remained stable for the following hundred hours. No copper(II), or other metal–ions, were determined in the crevice solutions, thus suggesting that within the investigated time the copper–rich α–phase dominated the NAB corrosion behaviour. Furthermore, results also indicated (ii) the low dissolved oxygen concentration within the crevice (since it promotes the oxidation of copper(I) to copper(II)) and (ii) that the local pH did not decreased below 4, where the NAB corrosion is controlled by the selective dissolution of the aluminium–, iron– and nickel–rich κ–phases.
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Kucita, Pawee. "The development of a wear resistance aluminium bronzes (Cu-Al-Fe) coating". Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/403720/.
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Aluminium bronze alloys (Cu-Al-Fe) with Al > 14 wt. % are known to have high wear resistance and low friction coefficient against ferrous metals thus making it an ideal material for forming dies application. However, the use of these alloys has been restricted by the high cooling rate required to prevent embrittlement of the alloy during production. The plasma transferred arc technique (PTA) is an attractive production technique that offers the required high cooling rate, however the resulting microstructure is strongly dependent on the composition change induced during deposition. Therefore to optimise the microstructure for application such as forming dies, thorough understanding of the effects of PTA induced composition change on the microstructure, wear and corrosion resistance properties are required. The composition change induced by PTA involves primarily an increase in Fe. Therefore, in the present research four aluminium bronze coatings with 9, 20, 27 and 35 wt. % Fe were produced from a gas atomized Cu-Al-Fe powder by deposition on to an E.N. 10503 steel substrate by PTA. Microstructure characterisation was carried out using complementary techniques involving SEM, EDS, XRD, EBSD and depth-sensing nano-indentation on etched and electro-polished specimen. The results show that Fe content above 9 wt. % leads to a phase change from the Cu3Al martensitic β1' to solid solution (Cu) phase. This is also accompanied by an increase in size of the Fe3Al intermetallic κ1 phase. The redistribution of Al solute during cooling was identified as the main factor for the observed phase change. These microstructure changes lead to a hardness increase from 4.9 GPa in the coating with 9 wt. % Fe to 5.6 GPa in the coating with 35 wt. % Fe, however hardness mapping using depth-sensing nano-indentation shows that in the high Fe content coating, the hardness distribution is not uniform. This is due to the large volume fraction of the intermetallic κ1 phase which has high hardness of ~7 GPa. The wear resistance of the coating was found to be strongly influenced by the Cu-rich matrix phase. In the coatings with 20, 27 and 35 wt.% Fe, delamination and abrasive wear are the dominant wear mechanisms. SEM observations show that pile-up of slip at the hard intermetallic phase leads to the formation of surface cracks. Coalescence of these cracks coupled with the adhesion between the coating and the ferrous counter material were found to be responsible for promoting delamination wear, which results in high wear rate. The coating with 9 wt.% Fe has the lowest specific wear rates of 2.11-2.87 x 10-4 mm3/Nm against AISI 316, 420 and 440 stainless steel. This is significantly lower than the specific wear rates of 5.95-15.36 x 10-4 mm3/Nm measured for the currently used AISI D2 tool steels at the same condition. This is due to the uniform hardness and retention of the martensitic β1' phase. The effects of PTA induced microstructure change on the corrosion resistance were investigated by electrochemical and immersion corrosion tests in an aerated 3.5 % NaCI solution. The results show that the corrosion resistance of the coating is strongly dependent on complete formation of Al2O3 protective layer. The Al content in the coating is a critical factor in the formation of the protective layer. In the coating with high Fe content where limited Al solutes are available, high corrosion rates of 300-400 x 10-3 mm per year were observed. The 9 wt.% coating which contains the highest Al solute, the lowest corrosion rate of 22.5 x 10-3 mm per year was measured. This corrosion rate is comparable to the more expensive and highly alloyed nickel aluminium bronze. Based on the results obtained in the present research, the coating with a martensitic β1' phase and submicron size intermetallic κ1 phase has the highest wear and corrosion resistance. Such a structure can be achieved by controlling the PTA parameters to minimize the composition change promoted by melting of the steel substrate during deposition. The results from the present research also highlight the importance of interface properties, which have been shown to have a significant influence on properties such as adhesion, wear and corrosion. As more composite materials are utilised, further understanding of the microstructure and properties near the interfaces between materials becomes ever more important. It is hoped that the methodology and results presented in this thesis will provide the initial groundwork for future experimental and modelling work on multiphase material.
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Jung, Mi-Hee. "Solubility studies on the NaAlO₂-NaNO₃-H₂O system". Master's thesis, Mississippi State : Mississippi State University, 2005. http://sun.library.msstate.edu/ETD-db/ETD-browse/browse.
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Kear, Gareth. "Electrochemical corrosion of marine alloys under flowing conditions". Thesis, University of Portsmouth, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369433.
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Anderson, Jonathan D. "Impacts of amending bauxite residue sands with residue fines for the establishment of vegetation on residue disposal areas /". Murdoch University Digital Theses Program, 2009. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20090831.155453.
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com, harriehofstede@yahoo y Henricus T. Hofstede. "Use of bauxite refining residue to reduce the mobility of heavy metals in municipal waste compost". Murdoch University, 1994. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20060815.143422.
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Use of bauxite refining residue to reduce the mobility of heavy metals in municipal waste compost.
Due to the adverse environmental impact of landfills and the lack of space for nearby population centres an unprecedented interest has developed in waste recycling with the objective to reduce the volume of waste disposed. Generally organic matter represents the largest fraction in the domestic waste stream including food, garden and paper waste.
In the past efforts have been made to process this organic fraction into muniapal compost.However contamination of the compost with heavy metals has in many cases resulted in the lack of suitable markets and subsequent closure of compost facilities. A study was undertaken and aimed at reducing the concentration and mobility of heavy metals in
municipal compost.
Bauxite refining residue ha; a high capacity to immobilise metals in soils through
precipitation, cation exchange and chemisorption (Fe- and Al- oxides).
The first step in the study was to assess the metal adsorption capacity of red mud by equilibrating red mud with metal solutions. Metal removal from solution proved very high.
Subsequently, the effect of red mud addition to municipal compost was studied in relation to metal mobility. In particular the interaction of metals with the mobile soluble organic fraction, the humic and fulvic acids, was investigated. It was found that most metals remained in the insoluble humin fraction and the metals in solution remained complexed to the soluble organic fraction. Red mud appeared to be able to adsorp fulvic and humic acids
and thus indirectly immobilise the metals in solution. Red mud did not appear to be able to transfer metals from the organic fraction to the mineral red mud fraction.
ft was kypothesised that, in order for the metals to be adsorped to red mud, the red mud needed to be present in the organic waste prior to composting. Metal adsorption to red mud is a rapid chemical reaction while metal complexation to the organic fraction takes a number of weeks, since it must be sufficiently oxidised to contain functional groups.
In order to verify this hypothesis, an installation with seven incubators was developed which allowed composting to be undertaken under computer controlled conditions and
monitored for temperature, airflow and carbon dioxide respiration. The incubators were filled with 10 kg of a mixture of grass clippings and sawdust. The first incubator functioned as a control. The contents of the rest of the incubators were spiked with the following
metals: Cd, Cr, Cu, Ni, Pb and Zn. In addition the contents of the 3rd - 7th incubators were amended with an increasing percentage of red mud, respectively 10,20,25,30 and 40 % by weight. After the mixture was composted, the metal mobility was reduced by approx. 80 - 99 %, depending on the metal. The mobility was assessed as leachable and plant available in relation to the total metal content. Red mud did not affect the composting process if < 40% red mud was added.
The next step was to compost municipal organic waste in a pilot plant (capacity 5 m3) using batches with and without red mud. Mixed waste was collected from 150 households and
the glass, metal and plastic fractions were removed bx- manual sorting. The rest was composted.
The red mud - compost had a relatively lower metal content and a reduced metal mobility compared to compost without red mud. The red mud - compost also had a 300 times higher
pH buffer capacity and 90%less soluble organic matter.
The addition of red mud prior to composting was found to reduce the concentration and mobility of metals in compost, improve the quality of compost as a soil conditioner, increased the resistance of the organic fraction against further breakdown and this process
thus adds value to both red mud and organic waste.
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Barros, Renato Araujo. "Influência da nitretação a plasma e carbonetação a laser nas propriedades tribológicas do par aço AISI/SAE 4340 e liga bronze-alumínio 630 /". Guaratinguetá, 2017. http://hdl.handle.net/11449/148983.
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Orientador: Antonio Jorge AbdallaCoorientador: Humberto Lopes Rodrigues
Coorientador doutorado sanduíche: Jean Denape
Banca: Marcelino Pereira do Nascimento
Banca: Cristina de Carvalho Ares Elisei
Banca: Rafael Humberto Mota de Siqueira
Banca: Rosinei Batista Ribeiro
Resumo: Os aços de ultra alta resistência como o aço 4340 tem sido amplamente utilizados pela indústria aeronáutica e aeroespacial em aplicações como trens de pouso de aeronaves e o veículo lançador de satélite brasileiro (VLS), além de um uso extensivo para diversos setores da indústria em geral. Isso se deve, em grande medida, às suas propriedades mecânicas. Este trabalho se propõe a avaliar as propriedades tribológicas do par aço 4340, inicialmente submetido ao tratamento térmico de têmpera e revenimento, e a liga bronze alumínio 630, utilizados em trens de pouso. Será estudado o comportamento destas estruturas após o aço ser submetido a tratamentos de superfície por nitretação a plasma e carbonetação a laser, como forma de melhorar seu desempenho com relação ao atrito e ao desgaste. Neste estudo foi escolhido o ensaio tipo pino-disco para simular a situação real de desgaste. Os discos foram confeccionados a partir do aço AISI/SAE 4340 e os pinos foram feitos da liga bronze-alumínio 630. Foram realizadas análises microestruturais das estruturas e das camadas de compostos formadas devido ao tratamento de superfície, Após os ensaios de desgaste foram feitas observações das superfícies através de microscopia e perfilometria óptica, microscopia eletrônica de varredura, difratometria de raios-X, testes de riscamento (scratching tests), dureza, observação de rugosidade e pesagem dos corpos de prova. Foram levantados os parâmetros do desgaste e alterações microestuturais devido à interaç... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Ultra high strength steels as 4340 steel has been widely used by the aerospace industry in applications such as aircraft landing gears and the Brazilian satellite launch vehicle (VLS), plus an extensive use for various sectors of the industry in general. This is due largely to their mechanical properties. This work aims to evaluate the tribological properties of 4340 steel pair, initially submitted to heat treatment of quenching and tempering, and aluminum bronze 630 alloy, used in landing gear. The behavior of these structures after the steel be subjected to surface treatment by plasma nitriding and laser carbonetation will be studied, as a way to improve its performance with respect to friction and wear. For this study, pin-on-disc test was chosen in order to simulate the real situation of wear. The discs were made from 4340 steel and pins were made of aluminium bronze 630 alloy. Micro-structural analyses were undertaken of the structures and compound layers formed due to surface treatment. After the wear tests surface observations were made through microscopy and perfilometry optical, scanning electron microscopy, x-ray diffractometry, x-ray tests, scratching tests, hardness, roughness and weighing of the specimens. Parameters of wear and microestuturals changes were raised due to interaction between the contact surfaces during rehearsals. Loss of mass was analyzed and curves of wear and friction related parameters were plotted in function of the slided distance and/or time of test. In the tests three test velocities were used: 0.5; 1.0 and 1.5 m/s. It was possible to calculate the wear rate for each pair and studied velocities. In general it was noted that the mechanisms of wear detected are similar for all conditions of the surface of the discs. The images show that the particles are bent on the disc, in the form of layers, ... (Complete abstract click electronic access below)
Doutor
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Barros, Renato Araujo [UNESP]. "Influência da nitretação a plasma e carbonetação a laser nas propriedades tribológicas do par aço AISI/SAE 4340 e liga bronze-alumínio 630". Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/148983.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Os aços de ultra alta resistência como o aço 4340 tem sido amplamente utilizados pela indústria aeronáutica e aeroespacial em aplicações como trens de pouso de aeronaves e o veículo lançador de satélite brasileiro (VLS), além de um uso extensivo para diversos setores da indústria em geral. Isso se deve, em grande medida, às suas propriedades mecânicas. Este trabalho se propõe a avaliar as propriedades tribológicas do par aço 4340, inicialmente submetido ao tratamento térmico de têmpera e revenimento, e a liga bronze alumínio 630, utilizados em trens de pouso. Será estudado o comportamento destas estruturas após o aço ser submetido a tratamentos de superfície por nitretação a plasma e carbonetação a laser, como forma de melhorar seu desempenho com relação ao atrito e ao desgaste. Neste estudo foi escolhido o ensaio tipo pino-disco para simular a situação real de desgaste. Os discos foram confeccionados a partir do aço AISI/SAE 4340 e os pinos foram feitos da liga bronze-alumínio 630. Foram realizadas análises microestruturais das estruturas e das camadas de compostos formadas devido ao tratamento de superfície, Após os ensaios de desgaste foram feitas observações das superfícies através de microscopia e perfilometria óptica, microscopia eletrônica de varredura, difratometria de raios-X, testes de riscamento (scratching tests), dureza, observação de rugosidade e pesagem dos corpos de prova. Foram levantados os parâmetros do desgaste e alterações microestuturais devido à interação entre as superfícies de contato durante os ensaios de deslizamento. Foi analisada a perda de massa e levantadas as curvas de desgaste e dos parâmetros relacionados ao atrito em função da distância percorrida e/ou do tempo de ensaio. Nos ensaios foram utilizadas três velocidades de ensaio: 0,5; 1,0 e 1,5 m/s. Foi possível o cálculo da taxa de desgaste para cada par e velocidades estudadas. De uma maneira geral constatou-se que os mecanismos de desgaste detectados são semelhantes para todas as condições de superfície dos discos. As imagens mostram que partículas do pino são deformadas sobre o disco, em forma de camadas, evidenciando o mecanismo de adesão. A carbonetação a laser criou uma camada rica em carbono com a presença de grafite que contribuiu para reduzir o coeficiente de atrito e o desgaste do pino, principalmente, para as velocidades de 0,5 e 1,0 m/s. A nitretação a plasma reduziu a perda de massa do disco e do pino, com indicativos de pequena perda de massa para todas as velocidades estudadas; a rugosidade e o aumento do coeficiente de atrito no par pino-disco para as velocidades de 1,0 e 1,5 m/s podem ter sido induzidas por alteração no tipo de desgaste, de adesivo para uma abrasão a três corpos.
Ultra high strength steels as 4340 steel has been widely used by the aerospace industry in applications such as aircraft landing gears and the Brazilian satellite launch vehicle (VLS), plus an extensive use for various sectors of the industry in general. This is due largely to their mechanical properties. This work aims to evaluate the tribological properties of 4340 steel pair, initially submitted to heat treatment of quenching and tempering, and aluminum bronze 630 alloy, used in landing gear. The behavior of these structures after the steel be subjected to surface treatment by plasma nitriding and laser carbonetation will be studied, as a way to improve its performance with respect to friction and wear. For this study, pin-on-disc test was chosen in order to simulate the real situation of wear. The discs were made from 4340 steel and pins were made of aluminium bronze 630 alloy. Micro-structural analyses were undertaken of the structures and compound layers formed due to surface treatment. After the wear tests surface observations were made through microscopy and perfilometry optical, scanning electron microscopy, x-ray diffractometry, x-ray tests, scratching tests, hardness, roughness and weighing of the specimens. Parameters of wear and microestuturals changes were raised due to interaction between the contact surfaces during rehearsals. Loss of mass was analyzed and curves of wear and friction related parameters were plotted in function of the slided distance and/or time of test. In the tests three test velocities were used: 0.5; 1.0 and 1.5 m/s. It was possible to calculate the wear rate for each pair and studied velocities. In general it was noted that the mechanisms of wear detected are similar for all conditions of the surface of the discs. The images show that the particles are bent on the disc, in the form of layers, showing the mechanism of adhesion. The laser carbonetation created a carbon-rich layer with the presence of graphite, which contributed to reduce the friction coefficient and pin wear, mainly for the 0.5 and 1.0 m/s velocities. The plasma nitriding reduced the loss in mass of the disk and pin, with indicative of small mass loss for all velocities studied; the roughness and the increase of the coefficient of friction in the couple pin-disc for the velocities of 1.0 and 1.5 m/s may have been induced by changes in the type of wear, from adhesive wear to a three-body abrasion.
CAPES: 99999.002441/2014-04
30
Boyer, Philippe. "Gravure de l'aluminium en plasmas halogénés basse pression-influence du facteur d'aspect". Toulouse, INSA, 1993. http://www.theses.fr/1993ISAT0002.
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Ce travail s'inscrit dans le cadre du developpement des filieres de fabrication de circuits integres prototypes cmos 0,5 et 0,35 m au centre national d'etudes des telecommunications de meylan (france telecom), et plus precisement de procedes de gravure de l'aluminium. Dans un premier temps, l'auteur presente les specificites de la gravure de l'aluminium, et montre les limites des reacteurs de gravure classique, fonctionnant dans un regime de pression intermediaire (100 mtorr). Cela a conduit au choix d'un reacteur de gravure basse pression (reacteur triode a confinement magnetique, 1 mtorr) dont les caracteristiques ont ete etudiees. L'auteur presente par la suite la demarche experimentale qui a permis de mettre au point un procede de gravure aluminium basse pression, utilisant un melange brome-chlore. Le procede issu de ce travail a demontre sa fiabilite et sa large fenetre de fonctionnement puisqu'il est utilise pour graver differentes metallisations a base d'aluminium (alliages, multicouches). L'apport plus specifique a la comprehension des mecanismes de gravure de l'aluminium a porte sur l'etude de la variation de la vitesse de gravure en fonction du facteur d'aspect. L'influence de la conductivite du masque, des parametres plasma tels que flux d'ions et flux de neutres, et de l'aspect du motif (trou, tranchee,. . . ) a ete etudiee. Ces resultats ont permis de developper un modele base sur l'ecrantage des flux; cet ecrantage est a la fois de nature geometrique (flux d'ions et de neutres) et electrique (flux d'ions)
31
Chin, Ti-Wei y 靳迪偉. "Study on the properties of nickel aluminum bronze and manganese bronze propeller materials". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/bv974a.
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碩士國立高雄科技大學
化學工程與材料工程系
107
The commonly used propeller materials nowadays are nickel-aluminum bronze, manganese bronze and aluminum bronze, among which nickel-aluminum bronze is more widely used because of its better physical characteristics than other two materials. This study is divided into three parts, the firstly the physical properties of nickel aluminum bronze and manganese bronze materials were inestigated and identified Then,the influence of the chemical characteristics on physical properties also examined, by spectroscopic instruments.can reveal the chemical compositions in the pass product or failed product and The use the technique of different chemical ingredients to improve their chemical properties, and enhance the excellent product performance, Finally after the inspection of the above two kinds of metallographic methods it was confirmed by the microstructure examination and the organization of metal and its distribution also revealed. It can be known that the increase in the content of beta phase will increase the tensile strength and hardness of the material, and decrease the toughness. Beta is also sensitive to relative stress corrosion in seawater. Accordingly,beta is kept correspondingly low to ensure adequate plasticity and corrosion fatigue resistance. When the content of alpha phase in nickel-aluminum bronze and manganese bronze is about 40 %, the properties of tensile strength, toughness and corrosion fatigue strength are the best.
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Lu, Chung-Hsien y 呂忠賢. "Investigation of the Mechanical Properties for Hot Pressing of Aluminum Bronze Matrix Composite". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/80927437184433841569.
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碩士華梵大學
機電工程學系
101
This paper mainly investigates the hot pressing of the aluminum bronze matrix alumina composites using the powders of copper, tin, nickel, iron, aluminum, alumina, etc. The mechanical properties of porosities, hardness, bending strengths, and microstructure for the aluminum bronze matrix composites were studied. The experiment results showed that the aluminum bronze matrix composites with the increase of the amount of iron and nickel resulted a higher open porosity and a lower close porosity and presented a larger hardness of the matrix. However, the alumina composites contain a too more amount of iron and nickel powders would cause a lower bending strength due to forming some weaker bonding among the iron, nickel, copper, aluminum under this hot pressing. Besides, adding alumina into the matrix displayed a poorer hardness and bending strength. This may be attributed to a higher porosity. Furthermore, the aluminum bronze matrix composites obtained after resin infiltration showed a smaller number of open porosity and a larger number of close porosity, which causes a higher hardness, bending strength and strain energy.
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HUANG, YIN-YAN y 黃垠諺. "Microstructure and Mechanical Properties of sputtrerd (TiZrHf)/(AlSiB)Nx Films Deposited on the Aluminum Bronze Worm Gears". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/z3rnu2.
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碩士國立勤益科技大學
機械工程系
107
In This study, the system was plated by reactive RF Magnetron Splash Plating TiZrHf/AlSiB multi-alloy metal and nitride films are discussed at different power, and the substrate temperature of the 400℃on the microstructure and mechanical properties of thin films. maintaining a constant temperature of 400 ° C on the aluminum bronze substrate,two three-spray sputtering gun modules were deposited by a co-deposition method, Ti33.3at% Zr33.3at% Hf33.3at% ternary alloy target power is fixed 400W,selected Al33.3at% Si33.3at% B33.3at% ternary alloy target variable power to 20w as the interval, by changing the power of the plating film thickness was in the range of 1μm ± 10%, in order to achieve optimum adhesion, and finally the mechanical properties are analyzed.The results show that with the increase of power,the TiZrHf/AlSiB Metal Film is a single FCC crystalline structure, and no precipitated phase is produced. Thin film growth in the preferred direction of the (200) plane, when the splash plating power of 40W, hardness up to the maximum 34GPa , Young's coefficient is 272GPa , the crystalline state is a typical columnar crystals, and the power is increased to 80W, Crystal State is changed to amorphous structure, but the hardness is very reduced. In terms of adhesion, when the splash plating power of 40W has a better adhesion, friction coefficient is also reduced, the friction coefficient value of 0.471, The friction coefficient value of the aluminum bronze substrate without splashing multi-alloy film is 0.522, which is compared with the splash plating TiZrHf/AlSiB Nitride film has a better mechanical properties, Therefore, the application in the worm wheel and worm can reduce the friction force, so the noise and energy consumption are reduced, temperature rise phenomenon is not easy to produce, the extension of aluminum bronze worm wheel service life.
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Chen, Hong Kui y 陳宏魁. "Study of BTA Addition on the Wear-Corrosion Behavior of Aluminum Bronze and AISI 4140 Steel in 3.5%NaCl solution". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/33871387469377779029.
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碩士清雲科技大學
機械工程系所
97
1,2,3-benzotriazole (BTA) could interact with the surfaces of copper and its alloy to form Cu-BTA film in corrosive environments, and has long been known as an efficient inhibitor for the general corrosion of copper and its alloy in many industry applications. Recently, the occurrence of intergranular corrosion (IGC) of copper in 3.5% NaCl solution in the presence of 1×10-3 M BTA was reported. Both cast and wrought aluminum bronzes offer a good combination of mechanical properties and corrosion resistance. Aluminum bronzes well known for its good sliding properties, is frequently applied as tool material in sheet metal forming (SMF) of stainless steel, e.g. for the production of washing, refrigeration and cooking equipment. The purpose of this study is to investigate the effect of BTA addition with different concentrations (1×10-3 M and 5×10-3 M) on the wear-corrosion protection ability of aluminum bronze sliding against AISI 4140 steel in 3.5% NaCl solution. The wear-corrosion experiment was performed by using a block-on-ring surface friction manner, aluminum bronze as the block and AISI 4140 steel as the friction ring. The wear conditions were under fixed rotation speed of 200 rpm and with different applied normal loads of 10g, 20g, 50g and 100g. The friction force was measured with respect to testing time during wearing test. The friction coefficient (µ) can be calculated by dividing the applied normal load. Also, the wear loss was measured by weighing the specimen before and after the wear-corrosion test. SEM was used to analyze the surface morphology of the specimens after wear-corrosion test. The experimental results indicated that in 3.5% NaCl solution without BTA addition, the friction coefficient and wear loss increased with increasing loads, and aluminum bronze showed the less wear loss than AISI 4140steel. Only a slight mechanical worn surface for aluminum bronze was observed, whereas AISI 4140 steel showed an serious wear-corrosion failure surface. As after BTA adding into 3.5% NaCl solution, both aluminum bronze and AISI 4140 steel exhibited an good ability for wear-corrosion protection. Especially, high BTA concentration showed a significant decrease of friction coefficient and wear loss, and then separate two parts, one is original material proceeding static electrochemistry potentiodynamic experiment that can prove BTA to have superior protection, another part is dynamic electrochemistry to wear with ceramics, and then to measure signal side anti-corrosion, the potentiodynamic show the date and curve, so we can know that BTA have good anti-corrosion and reduce the friction coefficient, weight loss.
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Wang, Hong-Yi y 王弘毅. "Microstructure and mechanical properties of an equimolar Al2O3-SiO2-TiO2-ZrO2 composite film on aluminum bronze alloy synthesized by the sol-gel technique". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/dpnsgb.
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碩士國立臺灣海洋大學
機械與機電工程學系
106
In this study, equimolar alumina-silica-titania-zirconia composite films were deposited on C95400 aluminum bronze alloy synthesized by the sol-gel technique. The compositions of the composite films were sintered at 600 ℃ under an argon gas atmosphere (oxygen-containing 9 ppm). By adding PO and PVP in precursor solution, adjusting pulling out speed, PVP content, baking temperature and coating times, discuss coating film material component, microstructure and surface morphology , and find suitable experiment condition. The thermal stability, structure and composition of composite films could be analyzed by using thermogravimetric analyzer (TGA), X-ray diffraction (XRD), Fourier transform infrared spectroscope (FTIR), Raman scattering spectroscope. The surface and mechanical properties of composite films were investigated by using scanning electron microscope (SEM) and scratch test. The results showed that added PO and PVP in films and suitable process could decrease its crack. Repeated coating films on substrate could promote the adhesion. A diamond-incorporated coating was successfully built by the micro-diamond dispersed precursor solution proposed by this work.
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Guedes, Fábio Alexandre Marques. "Estudo numérico do arrefecimento de um molde no processo de moldação de embalagens de vidro". Master's thesis, 2017. http://hdl.handle.net/10316/83062.
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Dissertação de Mestrado Integrado em Engenharia Mecânica apresentada à Faculdade de Ciências e TecnologiaA simulação numérica assume atualmente uma importância significativa nas áreas de projeto, investigação e desenvolvimento na medida em que os modelos computacionais permitem o estudo de modo versátil e detalhado de fenómenos físicos que, de outro modo, são por vezes de difíceis observação e análise. A sua utilização nas indústrias de processo, áreas cuja evolução está inevitavelmente dependente da experimentação e do conhecimento empírico, é hoje uma realidade. Deste modo, a indústria de produção de vidro de embalagem tem vindo a utilizar ferramentas de simulação computacional para otimizar alguns dos processos que mais influem no rendimento produtivo, nomeadamente, na modelação numérica dos fornos de fusão e da etapa de moldação. Porém, estes estudos de mecânica de fluidos computacional são ainda escassos e geralmente efetuados por empresas externas ligadas às áreas de projeto. Contrariando essa tendência, no presente trabalho recorre-se ao software Ansys® CFX para estudar numericamente o comportamento térmico de um molde de acabamento na fase de arrefecimento do processo cíclico de moldação de uma embalagem de vidro, uma garrafa de litro de cerveja. Com esse propósito, foram comparados moldes iguais de materiais diferentes: ferro fundido e bronze-alumínio. Verificou-se que o bronze-alumínio permite uma extração de calor mais eficaz durante o período de contacto entre o vidro e o molde, conduzindo a durações de moldação inferiores e aumentos de cadências de produção. Por interpretação das gamas de temperatura da moldação, foi elaborada uma análise aos pontos sensíveis à ocorrência de defeitos na garrafa moldada. Por fim, verificou-se que os regimes de escoamento do ar nos canais de arrefecimento são bastante expressivos, com elevados números de Reynolds e coeficientes de transmissão de calor. O estudo permitiu também a identificação de alguns aspetos de possível melhoria no projeto do molde.
Numerical simulation currently assumes a significant importance in the areas of design, research and development, allowing, in many cases, the obtention of results at a lower cost than through the more classic experimental approach. Its use in process industries, areas whose evolution is inevitably dependent on experimentation and empirical knowledge, is now a reality. Thus, the packaging glass manufacturing industry has been using computer simulation tools to optimize some of the processes that most influence the productive yield, namely, in the numerical modeling of the melting furnaces and the molding stage. However, studies with computational fluid dynamics are still scarce, usually carried out by external companies of the design areas. The present work uses Ansys® CFX software for a numerical study of the heat transfer processes taking place in the molding of glass bottles. For this study, two molding materials were considered: cast iron and aluminum-bronze. It has been found that aluminum-bronze allows more efficient heat extraction during the contact time between the glass and the mold, leading to lower molding times and increases in production rates. Potential locations for the occurrence of defects in the molded bottle were anticipated through the analysis of the temperature fields. Finally, it has been found that the air flow in the cooling channels are characterized by high heat transfer rates, at large Reynolds numbers. The study also allowed the identification of some points for improvement in the mold design.