High Temperature Compression Tests of Molybdenum-Rhenium Alloys and Constitutive Model Establishment with Internal State Variables
The flow behavior of Mo-14Re molybdenum-rhenium alloy at high temperature and its cross-scale characterization were investigated through high temperature compression test of the alloy bar which was carried out by Gleeble thermal simulation testing machine at the selected temperature of 1400,1500 and 1600 ℃ and the strain rate of 0.01,0.1,1 and 10 s-1.The results show that when the alloy is deformed at high temperature and low strain,the strain rate sensitivity factor increases gradually,and the plastic flow performance of the material becomes better;in the meantime,the two phenomena of stress hardening and softening exist simultaneously during deformation.On this basis,a cross-scale constitutive model was established.The flow stress characterization takes into account the resistance,thermal activation and the immobile dislocation of grain boundary effects.The microstructure evolution takes into account the grain size,dislocation density,dynamic recrystallization rate and crack volume fraction.The calculated values of yield stress,grain size and flow stress are in good agreement with the experimental results.It can be seen that the model can describe the rheological behavior and microstructure evolution of Mo-14Re molybdenum-rhenium alloy during high temperature deformation.
NETL
NSTL
万方数据
