Effects of solution treatment on high temperature deformation behavior of extruded Mg-0.35Y-2.17Nd-0.36Zr biomedical alloy

The high temperature deformation behavior of an extruded Mg-0.35Y-2.17Nd-0.36Zr (wt.%) alloy was investigated for biomedical application by employing compression tests in temperature range of 225-525 degrees C and strain rate range of 0.0003-0.03 s(-1). To study the significance of solute elements, the material was solution-treated before deformation. The low temperature yield strength of the as-extruded material significantly decreased after solutionizing process. A drastic change in the strength of solutionized alloy was recorded as the temperature was raised to 450 degrees C, which was attributed to the promotion of grain boundary sliding (GBS). It was evidently shown that the slip-to-twinning transition temperature did not necessarily coincide with the strength-drop temperature. Based on constitutive equations, deformation parameters and related activation energy for the experimental alloy have been determined, incorporating the strain-dependent material constants. The verification of predictability of the developed models indicates a good agreement between experimental and predicted data.