Enhancing creep properties of a hot-rolled Mg-4Y binary alloy via a new thought of inhibiting cross-slip

Highlights: • Pre-compression along TD is successfully applied to rolled Mg-4Y alloy. • Pre-compression induces two types of {10-12} twins and a few of basal dislocations. • Cross-slip is the dominant creep mechanism of NPC sample. • Pyramidal c + a slip is the dominant creep mechanism of PC sample. • Creep properties of rolled Mg-4Y alloy are enhanced by inhibiting cross-slip. -- Abstract: A new thought of enhancing the creep properties of a hot-rolled Mg-4 wt%Y binary alloy was reported in this work. Using various characterization methods, it was indicated that cross-slip composed of basal a and prismatic a dislocations was the origin of creep rupture for the homogeneous annealed alloy. But amazingly, cross-slip was successfully inhibited by performing a pre-compression and introducing {10-12} twins into this alloy. As a result, pyramidal c + a slip became the dominant creep mechanism and enhanced creep properties were obtained in the pre-compressed alloy. It is hoped that this new thought of inhibiting cross-slip can enrich the basic theories and extend the application fields of Mg alloys.