Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7989737 | International Journal of Refractory Metals and Hard Materials | 2018 | 10 Pages |
Abstract
Aiming at the contradiction between tribological and mechanical properties of traditional self-lubricating ceramic composites, an advanced self-lubricating ceramic composite with the addition of pure-metal coated solid lubricant powders was developed in terms of microstructural modification of the traditional composites. Core-shell structured h-BN@Ni powders were synthesized by electroless plating technique with hydrazine hydrate as reducing agent. Al2O3/(W,Ti)C/h-BN@Ni composite made by adding h-BN@Ni powders exhibited notable improvements in microstructure and mechanical properties as compared with Al2O3/(W,Ti)C/h-BN composite made by adding uncoated h-BN powders. EDS and TEM analyses showed that the Ni shell particles in the Al2O3/(W,Ti)C/h-BN@Ni composite concentrated around the h-BN core grains and were located at grain boundaries or within the matrix grains. Due to their flaky structure, the h-BN grains had orientation distribution in the as-prepared ceramic composites, which resulted in anisotropies in mechanical properties and tribological behaviors. Dry sliding friction test revealed that the Al2O3/(W,Ti)C/h-BN@Ni composite had lower friction coefficient and higher wear resistance than the Al2O3/(W,Ti)C/h-BN composite. The different h-BN release modes caused tribological behaviors of the friction surface perpendicular to the hot pressing axis (HPA) to be better than those of the friction surface parallel to HPA.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Guangyong Wu, Chonghai Xu, Guangchun Xiao, Mingdong Yi, Zhaoqiang Chen, Hui Chen,