Research on Superplasticity of 5A90-O Aluminum Alloy Sheet

The influence of temperature and strain rate on the 5A90-O had been researched by costant strain-rate tensile method. The result shows that, although 5A90-O is not an ideal superplastic material, under certain conditions, with a large extension rate, the maximum elongation is193.6%. The strain rate has a significant impact on the flow stress and tensile strength under T=375°C∼500°C. With the decrease of strain rate, the load is reduced. Another important factor that affects the flow stress of 5A90 is temperature. Under the same strain rate, the flow stress of 5A90 is lower with the temperature increase. We choose the Backofen law as the constitutive equation of 5A90, the best condition of 5A90 surperplastic deformation is T=400°C, ε = 0.005s⁻¹. (paper)