Current progress of research on heat-resistant Mg alloys: A review

With the increasing attention received by lightweight metals, numerous essential fields have increased requirements for magnesium (Mg) alloys with good room-temperature and high-temperature mechanical properties. However, the high-temperature mechanical properties of commonly used commercial Mg alloys, such as AZ91D, deteriorate considerably with increasing temperatures. Over the past several decades, extensive efforts have been devoted to developing heat-resistant Mg alloys. These approaches either inhibit the generation of thermally unstable phases or promote the formation of thermally stable precipitates/phases in matrices through solid solution or precipitation strengthening. In this review, numerous studies are systematically introduced and discussed. Different alloy systems, including those based on Mg-Al, Mg-Zn, and Mg-rare earth, are carefully classified and compared to reveal their mechanical properties and strengthening mechanisms. The emphasis, limitations, and future prospects of these heat-resistant Mg alloys are also pointed out and discussed to develop heat-resistant Mg alloys and broaden their potential application areas in the future.