Effects of pre-existing twins on the mechanical properties of Laves phase V2Hf-based alloy

Abstract

Twins have attracted much attention due to the significant effects on strengthening and toughening metallic and ceramic materials, while relevant research on twins in intermetallic Laves phases is rare despite their wide applications as structural and functional materials. Herein, a Laves phase V2Hf-based alloy V-14Hf-22Nb (at.%) was designed and twins were incorporated by precompression for probing the effects of pre-existing twins on the mechanical properties of Laves phase alloy. The results showed that the pre-existing twins not only prompted the twin growth during the secondary compression but also reacted with perfect dislocation in the V2Hf. Consequently, the compression strength of the alloy decreased from 2.13 GPa to 1.95 GPa, and the plastic strain of the alloy dropped from 13.75% to 12.20%. The results obtained were helpful for better understanding of the effects of pre-existing twins on the mechanical properties of Laves phase alloys.