Quasi-in-situ study on {10-12} twinning-detwinning behavior of rolled Mg-Li alloy in two-step compression (RD)-compression (ND) process

Abstract

Twinning-detwinning (TDT) behavior in a strongly basal-textured Mg-Li alloy during two-step compression (RD)-compression (ND) process was investigated using quasi-in-situ EBSD. TDT behavior and TDT variants selection were statistically discussed with the loading path for the first time. Non-Schmid twinning behavior was observed in the first step compression, owing to the local stress fluctuations by neighboring twins; in contrast, Schmid's law well predicted the detwinning variants selection. This asymmetrical TDT behavior was first investigated to date related with the strong basal texture and loading path. Besides, with the progress of compression, Schmid factors for twinning demonstrated a decreasing tendency; however, those for detwinning during the second step displayed an abnormally increasing trend, fundamentally stemming from prior twinning behavior.

Keywords

• Twinning-detwinning
• Mg-Li alloy
• Quasi-in-situ
• Biaxial loading