The synchronous improvement of the strength and plasticity of Ni alloys assisted by vacancies

In this study, a synchronous improvement of the strength and plasticity (SISP) of Ni and Ni-Si alloys was found through introducing supersaturated vacancies into the microstructure. Detailed observations show that these vacancies tended to aggregate to form Frank loops, which impede dislocation annihilation and increase the strain-hardening capability of Ni and Ni alloys. This finding put forward a new approach for simultaneously improving the strength and plasticity of metallic materials. Finally, the influence of the quenching temperature and Si content on this SISP effect was discussed.