Structure and High Temperature Friction and Wear Behavior of Carbonaceous Mesophases Doped with Metallic Element Nickel (Ni) through Mechanical Alloying

Incorporation of metallic element Ni into the coal tar pitch-derived carbonaceous mesophase(CM) was performed through mechanical alloying in a high energy ball mill apparatus.The structures for the raw,as-milled and Ni-doped carbonaceous mesophases were characterized by X-ray diffraction and Laser-Raman spectroscopic techniques,and the friction and wear behavior for the CMs were investigated using a SRV high temperature friction and wear tester.Results show that,the Ni-doped CM through mechanical alloying shows a drop in the crystallinity and a decrease in the size of graphite planar micro-crystals,implying a transition to the amorphous structures caused by the mechanical alloying.In addition,the CMs displayed a high temperature anti-friction and wear resistant effect,and,compared with the CMs without mechanical alloying,the Ni-doped CM through mechanical alloying can provide more evident and longer time-lasting high temperature anti-friction and wear resistant effect.Raman spectroscopic examination of the worn 45~# steel surfaces indicated a variation in the microcrystalline planar size(La) for the CMs generated by tribo-induction,and the chemical identification by XPS of the worn 45~# steel surfaces confirmed the chemical reaction between the Ni element and the tribo-surfaces.Therefore,it can be assumed that there probably exists some correlation between the variation in the microcrystalline planar size(La) for the CMs generated by tribo-induction and its high temperature anti-friction and wear resistant effect.