Solid Lubrication with Carbon Onions at High Temperature in Vacuum

摘要

Solid lubricant performance of carbon onions prepared from diamond nanoparticles through a heat treatment at 1700℃ have been examined at high temperatures up to 300℃ in air and vacuum. Sliding friction between a silicon disk on which carbon onions were dispersed and a stainless steel ball was measured by means of ball-on-disk type friction testing. Friction coefficients in vacuum decreased with temperatures and became stable above 100℃ for longer service life. On the contrary to this, friction coefficients in air increased with temperatures despite Raman spectroscopic analysis and thermogravimetric analysis showed that the structure of carbon onions were stable in air up to 300℃.