TY - GEN
T1 - Grain refinement during superplastic deformation of coarse-grained Al-Mg-Cu alloys
AU - Cruz-Palacios, M. I.
AU - Hernández-Silva, D.
AU - Barrales-Mora, L. A.
AU - García-Bernal, M. A.
PY - 2006
Y1 - 2006
N2 - In the present study the superplastic behavior of Al-6%Mg-0.5%Cu and Al-8%Mg-0.5%Cu in a coarse grain size condition has been studied. The alloys are melted in an electrical furnace under argon atmosphere. The ingots (25 mm thick) are homogenized at 400°C during 72 h and then rolled at 430°C to a thickness of 5 mm. The mean grain size after rolling is 55 μ for the 6%Mg alloy and 61 μm for the 8%Mg alloy. Tensile test specimens are machined from the rolled plate in the rolling direction. Strain-rate-change tests at temperatures between 300 and 450°C and strain rates between 1×10 -4 and 1×10-1 s-1 are carried out to determine the strain rate sensitivity of the flow stress. Finally, elongation to failure tests are conducted at temperatures and strain rates where the alloys show a high strain rate sensitivity. Elongations higher than 390 % are obtained for the 8%Mg alloy. It is observed that the grip regions of the deformed samples show coarser grains than the regions near to the fracture surface. This means that grain refinement takes place during deformation, suggesting that the principal deformation mechanism is dislocation creep.
AB - In the present study the superplastic behavior of Al-6%Mg-0.5%Cu and Al-8%Mg-0.5%Cu in a coarse grain size condition has been studied. The alloys are melted in an electrical furnace under argon atmosphere. The ingots (25 mm thick) are homogenized at 400°C during 72 h and then rolled at 430°C to a thickness of 5 mm. The mean grain size after rolling is 55 μ for the 6%Mg alloy and 61 μm for the 8%Mg alloy. Tensile test specimens are machined from the rolled plate in the rolling direction. Strain-rate-change tests at temperatures between 300 and 450°C and strain rates between 1×10 -4 and 1×10-1 s-1 are carried out to determine the strain rate sensitivity of the flow stress. Finally, elongation to failure tests are conducted at temperatures and strain rates where the alloys show a high strain rate sensitivity. Elongations higher than 390 % are obtained for the 8%Mg alloy. It is observed that the grip regions of the deformed samples show coarser grains than the regions near to the fracture surface. This means that grain refinement takes place during deformation, suggesting that the principal deformation mechanism is dislocation creep.
KW - Aluminum alloys
KW - Superplastic materials
KW - Superplasticity
UR - http://www.scopus.com/inward/record.url?scp=35748946059&partnerID=8YFLogxK
U2 - 10.4028/0-87849-993-8.75
DO - 10.4028/0-87849-993-8.75
M3 - Contribución a la conferencia
SN - 0878499938
SN - 9780878499939
T3 - Materials Science Forum
SP - 75
EP - 80
BT - Advanced Structural Materials II - Proceedings of the Advanced Structural Materials Symposium of the Annual Congress of the Mexican Academy of Materials Science
PB - Trans Tech Publications Ltd
T2 - Advanced Structural Materials Symposium of the Annual Congress of the Mexican Academy of Materials Science, 2004
Y2 - 22 August 2004 through 26 August 2004
ER -