Preparation, mechanical properties, and high-temperature wear resistance of Ti-Al-B alloy

Abstract

Ti-Al matrix alloy reinforced with a high content of boron was fabricated by using a high-temperature alloying method and powder metallurgy technique (P/M). The preparation method of Ti-Al-B alloying powder was put forward. Phases, microstructure, and mechanical properties of the alloys were investigated. Wear and friction performance were studied by using a ball-on-disc tribotester sliding against a Si3N4 ceramic ball from 23 °C (room temperature) to 900 °C. The Ti-Al-B alloy had a higher specific strength than that of the Ti-Al alloy. The boron element obviously enhanced the wear resistance and mechanical properties of the alloys because of the formation of borides (TiB2 and AlB2) in matrices and the stable oxide film on the wear tracks. Friction coefficients of alloys were independent of the boron element. The wear mechanisms of the alloys transferred from fatigue wear to oxidative wear with the increase in temperature.