Cooperative enhancement of mechanical and tribological properties through tailoring TiN transition interface in boron nitride nanosheets reinforced copper composites
Zhonghua Li, Liang Liu, Xin You, Jianhong Yi, Rui Bao, Ming-Yi Zhu, Song Lu, Junjun Pai
Abstract
Abstract Strengthening interface bonding between boron nitride nanosheets (BNNS) and copper matrix is an essential prerequisite for exploiting a new generation of copper matrix composites (CMCs) with high strength and wear resistance. Herein, BNNS/Cu composites were fabricated by the powder metallurgy route, matrix‐alloying (adding 1.0 wt% Ti) strategy was adopted to improve the interfacial wettability and strengthen interface adhesion. A typical “sandwich”‐like multiply interface structure involving TiN transition layers, BNNS and Cu matrix had been well constructed through the rational heat treatment (900 °C for 120 min). Additionally, nano‐sized TiB whisker was in situ formed in the vicinity of the interface, it had linked the BNNS‐Cu‐TiN multiply interface, which played a role of “threading the needle” and significantly strengthened the multi‐interfaces bonding. This specific interface structure was finely characterized, and the formation mechanism of solid‐state interfacial reaction feature was proposed. The results demonstrated that the ultimate tensile strength (UTS) of BNNS/Cu‐(Ti)‐900 °C increased from 248 to 530 MPa (increased by 114%), and the coefficient of friction (COF) decreased from 0.51 to 0.28 than pure Cu. This work highlights the importance of interface configuration design, which contributes to the development of CMCs with prominent comprehensive properties.