THERMAL DEFORMATION BEHAVIOR OF HIGH-PURITY RARE EARTH METAL DYSPROSIUM

High-purity rare earth metal dysprosium was subjected to a single-pass thermal compression test at temperatures ranging from 300 °C to 700 °C and strain rates ranging from 0.1 s–1 to 10 s–1 using an MMS-200 thermal simulation testing machine. The true stress-strain curves, macro and microstructure of dysprosium were analyzed, leading to the establishment of processing maps and constitutive equation for dysprosium. Results revealed that the stress of dysprosium decreased with increasing deformation temperature and decreasing strain rate. Moreover, as the strain rate reached 5 s–1, the stress-strain curve gradually transitioned from dynamic recovery to dynamic recrystallization, with a more pronounced softening behavior observed at higher strain rates. Based on the processing diagram and sample microstructure analysis, it was determined that the optimal deformation range for dysprosium is between 350 °C and 500 °C at a strain rate of 1–10 s–1.