Thermodynamic Database Development for Mg Alloys with RE Elements and Applications to Mg Alloy Design

Abstract

Rare earth (RE) elements are often added to Mg-based alloys in order to improve creep resistance and strength at elevated temperature by forming stable precipitates with Mg (MgxREy), Al (AlxREy) or Zn (ZnxREy). Thermodynamic models and databases can provide invaluable information to elucidate the complex precipitation behaviors involving RE. In the present study, recent progress of Mg alloy database development with Fact Sage toward adding RE elements, including the systems Mg-RE and Al-RE (RE = La, Ce, Pr, Nd, Y, Sc, ...), and a number of Mg-Al-RE, Mg-Zn-RE and Mg-Mn-RE systems (RE = La, Ce, Y, Sc), is presented. Applications of the newly developed database to the Mg alloy design are also illustrated.