@article{CHEN2022, 
author = {Shu-na CHEN and Hengzhong FAN and Yunfeng SU and Jicheng LI and Junjie SONG and Litian HU and Yongsheng ZHANG},
title = {Bioinspired PcBN/hBN fibrous monolithic ceramic: High-temperature crack resistance responses and self-lubricating performances},
year = {2022},
journal = {Journal of Advanced Ceramics},
volume = {11},
number = {9},
pages = {1391-1403},
keywords = {self-lubricating composite ceramic, bioinspired structure, resistance curve (R-curve), high-temperature property, friction and wear},
url = {https://www.sciopen.com/article/10.1007/s40145-022-0618-y},
doi = {10.1007/s40145-022-0618-y},
abstract = {The high strength and toughness of natural materials are mainly determined by a combination of mechanisms operating at different length scales, which can be used as a strategy to reduce the intrinsic brittleness of ceramics. Inspired by the architectures of bamboo, the polycrystalline cubic boron nitride/hexagonal boron nitride (PcBN/hBN) fibrous monolithic ceramics with a long fiber arrangement structure was constructed with PcBN fiber cells and hBN cell boundaries, and its crack resistance responses and tribological performances were investigated. The composite ceramic failed in a non-brittle manner with the rising resistance curve (R-curve) behavior, which was attributed to multiscale crack effects in the hierarchical architecture. The maximum crack growth toughness was extremely high (approximately 21 MPa·m1/2), corresponding to a 270% increase over the crack initiation toughness. Excellent fracture resistance could be retained even above 1000 ℃. Moreover, the composite ceramic exhibited low and stable friction coefficients (approximately 0.33) when paired with a Si3N4 pin at high temperature (1000 ℃), owing to the lubrication function of hBN cell boundaries with weak van der Waals forces and a small amount of liquid B2O3 produced. As a result, a synergistic improvement of mechanical and tribological properties at high temperature (1000 ℃) was realized by combining bionic structure and tribological design. It provides important theoretical and technical support for expanding the application of self-lubricating composite ceramics in harsh environments.}
}