Investigation of deformation behavior, microstructure evolution, and hot processing map of Mo-14Re alloy single crystal

The hot deformation behavior of the 〈111〉 − oriented Mo–14 wt% Re (Mo-14Re) alloy single crystal was comprehensively investigated. Uniaxial compression tests were conducted at temperatures ranging from 1100 to 1400 °C and strain rates ranging from 0.01 to 10 s−1. Based on the obtained flow stress curves and an Arrhenius-type constitutive relation, a strain-compensated Arrhenius model was established for the 〈111〉 − oriented Mo-14Re alloy single crystal to describe its flow stress accurately. The microstructural characteristics of the deformed single crystals under various deformation conditions were examined using electron backscatter diffraction (EBSD). The results indicate that the 〈111〉 − oriented Mo-14Re alloy single crystal retained its single crystal structure across the entire tested range of temperatures and strain rates. The EBSD features observed at high temperatures and lower strain rates are consistent with dynamic recovery as the primary softening mechanism. Based on the dynamic material model, a hot processing map for the 〈111〉 − oriented Mo-14Re alloy single crystal was constructed over the strain range of 0.3 to 0.69. The correlation between microstructural evolution and the stability regions in the processing map suggests that, within the experimentally investigated conditions, the parameter windows of 1150–1300 °C/1–10 s−1 (at a true strain of 0.3) and 1200–1300 °C/0.1–0.01 s−1 (at true strains of 0.4–0.69) represent the optimal hot-processing window for the 〈111〉 − oriented Mo-14Re alloy single crystal.