Effect of rolling temperature on microstructure and mechanical properties of hot-rolled Mg-Al-Ca-Zn-Mn alloys

Abstract

In order to address the problems of traditional magnesium alloys, such as the easy formation of basal texture and poor plasticity at room temperature, a multivariate micro alloyed Mg-1Al-0.9Ca-0.5Zn-0.4Mn material has been designed by taking advantage of the unique role of solute atoms such as Ca. The effects of its rolling process on grain size, second phase, texture, and tensile properties were compared and analyzed. The results show that the rolling temperature will significantly change the organization and properties: a small number of large-sized reticulate phases, linear phases, and granular phases will exist along the rolling direction inside the Mg-1Al-0.9Ca-0.5Zn-0.4Mn alloy. When the rolling temperature is raised, it will change the number and size of the second phase and microstructure morphology. For three plates rolled at 300°C, the best-combined strength-plasticity mechanical properties were presented in this work; elongation is 2.5%, tensile strength is 167 MPa, and yield strength is 146 MPa along the RD, respectively. Besides, some larger-sized phases still exist in this alloy, which affects its mechanical properties.