Development of a flow stress model for metals using the strain rate /temperature superposition principle

The stress-strain response of metallic materials and alloys is influenced by the temperature at which deformation occurs and by the loading rate. To model this behavior under a wide range of strain rates and temperatures we propose to use the strain rate / temperature superposition principle: an increase in temperature will have the same effect on the yield stress as a decrease in strain rate. This type of approach has been recently proposed to model the yield behavior of solid polymers. Here we show that this approach can be extended to model the yielding and flow stress evolution in ductile metals. For a wide range of temperatures and strain rates, the superposition principle is applied for different metals such as copper and high strength steel. This comparison showed a good agreement with the experimental data found in the literature.