Influence Of Nitrogen Ion Implantation Fluences On Surface Structure And Tribological Properties Of Sic Ceramics In Water-lubrication

摘要

Nitrogen ions were implanted into SiC ceramics by using ion implantation technology (N~+-SiC). The surface structure and chemical bonds of N~+-SiC ceramics were determined by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), and their nanohardness was measured by nanoindenter. The friction and wear properties of the N~+-SiC/SiC tribo-pairs were investigated and compared with those of SiC/SiC tribo-pairs in water using ball-on-disk tribo-meters. The wear tracks on the N~+-SiC ceramics were observed by non-contact surface profilometer and scanning electron microscope (SEM) and their wear volumes were determined by non-contact surface profilometer. The results show that the N~+-SiC ceramics were mainly composed of SiC and SiCN phase and Si-N, C-C, C=N and C-N bonds were formed in the implantation layer. The highest hardness of 22.3 GPa was obtained as the N~+-SiC ceramics implanted at 50 keV and 1 × 10~(17) ions/cm~2. With an increase in nitrogen ion fluence, the running-in period of N~+-SiC/SiC tribo-pairs decreased, and the mean stable friction coefficient decreased from 0.049 to 0.024. The N~+-SiC ceramics implanted at 50 keV and 5 × 10~(17) ions/cm~2 exhibited the excellent tribological properties in water. In comparison of SiC/SiC ceramic tribo-pairs, the lower friction coefficient and lower wear rate for the N~+-SiC/SiC tribo-pairs were acquired.