Microstructure and high-temperature tensile properties of Ti₂AlNb/TA15 laminated composites prepared by vacuum hot pressing

In order to improve the intrinsic brittleness of Ti₂AlNb alloy without sacrificing its high-temperature performance, a composite material was prepared by combining it with high-temperature titanium alloy TA15 using vacuum hot pressing. The effects of different hot pressing temperatures on the microstructure and tensile properties of Ti₂AlNb/TA15 laminated composite materials were investigated. The results show that the pore defects in the interface layer gradually decrease with the increase of the hot pressing temperature. A defect-free metallurgical bonding interface can be achieved at temperatures of 1050°C and above. The thickness of the interface reaction layer increases with the rise of the hot pressing temperature. Under the diffusion conditions at 1050℃ and above, a transition layer of certain width formed between the reaction zone and the Ti₂AlNb layers, which improve the properties of the interface bonding. Tensile tests indicate that the room and high-temperature tensile properties of the Ti₂AlNb/TA15 laminated composite material are significantly improved compared with Ti₂AlNb alloy. The laminated composite material under the hot pressing temperature condition of 1050℃ exhibits excellent comprehensive performance, with a high-temperature tensile strength and strain of 667.85 MPa and 16.2%, respectively.