Cavitation during superplastic deformation of modified 5083 Al
Sponsor:
General Motors Corporation
Cavitation has been an important consideration in fabricating complex metal parts by superplastic forming processes. The basic processes leading to cavitation failure at working temperatures are nucleation, growth, and coalescence of cavities. The objectives of the project include: (1) the understanding of the deformation behavior |
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Low temperature superplasticity in submicrocrystalline (SMC) materials
Sponsor:
Dept of Energy
Research on superplaticity in metals have clearly established the importance of microstructural evolution combined with several phenomena: (1) dislocation emission and absorption at and near grain boundaries; (2) concurrent grain growth and (3) grain boundary sliding (GBS) during deformation. The combined evolutionary aspects of these |
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Novel lightweight open cell metal foam process and resulting properties
Sponsor:
U.S. Office of Naval Research
A new low cost process has been developed for fabricating both stochastic and periodic open cell metal foam structures by direct deposition of solidifying liquid wires, droplets and spray, and simultaneously welding them in-situ. The process is capable of producing a dide range of pore |
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Fabrication and creep studies on open cell nickle structures
Sponsor:
ONR, DARPA/NIST
Cellular Ni-base alloy structures have potential for light to medium load bearing applications at elevated temperatures as these structures may be actively cooled by fluid flow. In this study open-cell Ni structures were fabricated using two different processes. A process to create honeycomb cells was |
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Elastic and Inelastic Recovery after Plastic Deformation of DQSK Steel Sheet
Sponsor:
US Dept of Commerce
Strain recovery after plastic prestrain and associated elastic and inelastic behavior during loading and unloading of DQSK steel sheet are measured. Average tangent modulus and Poisson’s ratio during unloading and reloading are found to differ from their elastic values in the undeformed state, and they |
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Inelastic effects on springback in metals
Sponsor:
DOE
Springback from the formed state has been a subject of major concern in the design of sheet metal panels. The amount of springback is generally estimated by assuming an entirely elastic recovery process and using the established values of elastic modulus and Poisson’s ratio. It |
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MICROSTRUCTURAL EVOLUTION DURING SEVERE DEFORMATION OF AZ31 MAGNESIUM ALLOY UNDER NON-ISOTHERMAL PROCESSING CONDITIONS
Sponsor:
NSF
Large plastic deformation was imparted to Mg alloy plate AZ31B by compressing along in-plane directions, in progressive stages below 300ºC, via non-isothermal processing method and under superimposed hydrostatic pressure. It was shown that by progressively lowering the deformation temperature, microstructures of ultra-fine grain size, approaching |