Modeling the constitutive relationship of powder metallurgy Al–W alloy at elevated temperature

• Hot compression tests for the PM Al–W alloy are carried out.
• The flow behavior of Al–W alloy is characterized based on the stress–strain curves.
• The Arrhenius-type constitutive model of Al–W alloy at a certain strain is developed.
• The developed model has a good prediction of flow stress.

The deformation behavior of Al–W alloy was researched with isothermal compression tests at various deformation temperatures and strain rates to evaluate the deformation activation energy and to develop the constitutive relationship equation, which is in pursuit of revealing the dependence of the flow stress on the strain, strain rate and deformation temperature. The compression tests were conducted in the temperature range between 420 and 570 °C and at strain rates between 0.001 and 5.0 s−1. With the help of determination of related material constants (such as A, β and α) and activation energy Q (451.15 kJ mol−1), the Arrhenius-type constitutive relationship equation of Al–W alloy is developed. It was found that the correlation coefficient R and the AARE is 0.997% and 4.08%, respectively. The results show that the Arrhenius-type model, which considers the combined influence of strain rate and deformation temperature, is able to provide the accurate prediction of high temperature flow stress for the researched alloy.