Adjustable room temperature deformation behavior of Mg-Sc alloy: From superelasticity to slip deformation via TRIP effect

This study investigated the transformation-induced plasticity (TRIP) effect in Mg-Sc alloys with beta single-phase (body-centered cubic) structure. A Mg-19.8 at% Sc alloy showed fracture strain of similar to 53 % accompanied by necking propagation with increasing the tensile strain at room temperature. An X-ray diffraction analysis and transmission electron microscopy observations confirmed the existence of a hexagonal close-packed phase beside the beta matrix phase during and after the tensile test; this indicates a strain-induced martensitic transformation, i.e., the TRIP effect induced superior ductility. Moreover, the study revealed a threshold Sc content of similar to 19.5 at% Sc at which the deformation behavior at room temperature changes from super -elasticity to TRIP. The TRIP Mg-Sc alloys exhibited fracture strain from 45 % to 66 % and ultimate tensile strength (UTS) above 220 MPa to overcome the tradeoff between the fracture strain and UTS of conventional Mg alloys.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

This study investigated the TRIP effect in Mg-Sc alloys with a beta single-phase structure. The results showed that the presence of a hexagonal close-packed phase led to a strain-induced martensitic transformation, resulting in superior ductility. The Mg-Sc alloys exhibited high fracture strain and ultimate tensile strength, overcoming the limitations of conventional Mg alloys.