Achieving high strength and large ductility via Zr-rich stripes in Ti-15Zr alloy

• Published in: Materials letters 2022-07, Vol.318, p.132194, Article 132194
• Main Authors: Tang, Hanchun, Liu, Yong, Liu, Chaoqiang, Zhao, Dapeng, Song, Min
• Format: Article
• Language: English
• Subjects: Deformation and fracture; Ductility; Elongation; Grain boundaries; Hot extrusion; Materials science; Mechanical properties; Mechanical property; Microstructure; Powder metallurgy; Ti-Zr alloy; Titanium base alloys; Ultimate tensile strength; Yield strength; Zirconium
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2022.132194

•Ti-15Zr alloy prepared by powder metallurgy includes α single-phase with Zr-rich stripes.•The Ti-15Zr alloy has a good combination of strength and ductility.•High strength of the alloy is ascribed to the hindrance effect of Zr stripes.•Good ductility of the alloy is attributed to the occurrence of slip transmission across Zr stripes. The microstructures and mechanical properties of Ti-15Zr alloy (wt.%) prepared by powder metallurgy and hot extrusion were investigated. The alloy is comprised of α single-phase with Zr-rich stripes distributed at both intra- and inter-granular. The alloy has a tensile yield strength of ∼ 773 MPa, an engineering ultimate tensile strength of ∼ 874 MPa, and a total elongation of ∼ 28.6%. The good combination of strength and ductility is attributed to the Zr-rich stripes, since they could hinder the movement of dislocations and strengthen the grain boundaries but cannot limit their movement completely, namely, slip transmission could occur across them. Our findings provide a new way to strengthen titanium alloys without sacrificing ductility.