Microstructure, Mechanical Properties, and Corrosion Behavior of Hot‐Rolled Ti‐25Zr‐xY Alloys

Abstract

A series of Ti‐25Zr‐xY alloys are prepared by a vacuum arc melting furnace. Then, the Ti‐25Zr‐xY alloys are hot‐rolled by a multi‐pass rolling process. The mechanical properties and corrosion behavior of hot‐rolled Ti‐25Zr‐xY alloys were investigated using microscopic characterization. The results show that the microstructure of the alloys is mainly composed of α and α‐Y phases. The particle size of the second phase α‐Y increases with the increase of the Y element. When Y content reaches 0.4%, the alloy exhibits excellent mechanical properties (σ 0.2 = 930 ± 10 MPa, ε f = 10.16 ± 0.3%). The precipitation of the second phase and the presence of metal compounds are responsible for reducing the corrosion resistance of hot‐rolled Ti‐25Zr‐xY alloys. The corrosion behavior of the alloys in chlorine solution is sensitive to the Y content, with Ti‐25Zr‐0.1Y alloy having the best corrosion resistance. The erosion sensitivity of Zr and the precipitation of Y are responsible for the observed pitting corrosion phenomenon.