Effect of phase transformation on the ductile to brittle transition behavior of Ti–V–Nb–Zr body-centered cubic high-entropy alloys at elevated temperatures

• DOI: 10.1016/j.jmrt.2023.09.289
• Publication Date: 2023-10-04T08:12:41Z
• Authors: Yan Jiang; Yirong Liu; Min Chen; Xuefeng Zhang; Longfei Zeng; Zhiqiang Jiang; Jiaping Han; Xuan Xiao
• Keywords: Ductility (Earth science); Brittleness; Work hardening; Tensile testing; Solid solution strengthening

Single-phase body-centered cubic (BCC) lightweight Ti-V-Nb-Zrx solid-solution alloys were fabricated by reducing the Zr concentration within range of 0–5 at% to improve mechanical properties equimolar TiVNbZr alloy at elevated temperatures. The Zrx indeed exhibited greater strength above 800 °C than TiVNbZr, but some special responses occurred °C: (ⅰ) superficial cracks with different lengths and amounts along high-angle grain boundaries (HAGBs) on compressed sample surface, (ⅱ) near-brittle fracture tensile stress-strain curves. Based analysis deformed undeformed local stress phase transformation responsible for difference in compression behavior, atmospheric oxygen, deformation localization mainly °C. Phase promote dispersion, combined better oxidation resistance, which make Zr-containing fractured via transgranular mode test. In particular, Zr3 work hardening ductility. alloys, it was found that RT 600 °C, atomic size (δ) governed strength; from 1000 δ melting temperature (Tm) co-operatively 1200 independent δ, dependent Tm. have medium a small loss high temperatures, are suitable various processing methods.