Anisotropic Mechanical Property-Induced Ductilization (AMID) – A New Mechanism to Simultaneously Improve the Strength and Ductility of Multiphase Alloys

We recently proposed a new mechanism to simultaneously improve the strength and ductility of multiphase alloys, named “Anisotropic mechanical property-induced ductilization (AMID)”. In this paper, the variations in tensile deformation behavior of Mg/LPSO extruded alloys depending on the volume fraction of the LPSO phase were examined, to deepen the understanding on AMID. As expected, the work-hardening rate of the Mg/LPSO two-phase extruded alloy increased as increasing in the volume fraction of LPSO phase. This demonstrates the validity of the AMID mechanism. However, the increase in the volume fraction of the LPSO phase decreased the elongation, even though the work-hardening rate was increased in them. The present study revealed that an appropriate amount of Mg grains is necessary to obtain the effect of AMID in improving the uniform elongation of the alloy, by the suppressing the development of microcracks formed in the LPSO phase grains into macroscopic fracture.