New model of the constitutive relationship of 2A70 aluminum alloy

To study the flow rules of the 2A70 aluminum alloy deformed at high temperature, a series of isothermal compression tests were performed on a Gleeble-1500 thermal simulator. On the basis of experiment data, a new constitutive model of the 2A70 aluminum alloy was constructed using an amended BP artificial neural network. True strain, strain rates and temperatures were input parameters of the model, while flow stress was the only output parameter. Computer results showed that the relative error of the new model was less than ±3% for the sampled data while it was less than ±6% for the non-sampled data. It is evident that the constitutive model constructed by BP ANN can accurately describe the flow rule of the 2A70 alloy hot deformation.