The intrinsic high ductility in B2 intermetallic compound YAg: Causality clarified by ab initio study

Tuning the plasticity of intermetallic compounds to expand the application field has always been the expectation of researchers. As the ultra-ductile intermetallic compound, the existence of YAg proves the possibilities of high plasticity in intermetallic compounds. To further dig high plastic intermetallic compounds, the micromechanism of extraordinary intrinsic ductility of YAg was analyzed in atomic scale, and was concluded in three aspects: i. activated shear paths with low ideal shear strengths in {110}< 110 > and {110}< 111 > slip systems; ii. caterpillar crawl of Ag-Ag bonds makes B2 structure able to withstand large strain; iii. the hybrid peak of d-band electrons to be narrow and far below from Fermi level, that is the key to form non-localization bonds which can withstand large stretches. These insights are expected to provide new ideas for finding high ductility interme-tallic compounds.

Automated summary

Tuning the plasticity of intermetallic compounds is of great interest to researchers. The discovery of the ultra-ductile YAg compound demonstrates the possibility of high plasticity in these compounds. By analyzing the micromechanism of YAg's exceptional intrinsic ductility at the atomic scale, it was found that activated shear paths with low ideal shear strengths, caterpillar crawl of Ag-Ag bonds, and the hybrid peak of d-band electrons play key roles in enhancing the ductility. These insights offer new ideas for finding high ductility intermetallic compounds.