机械合金化法掺杂镍的碳质中间相结构及其高温摩擦磨损特性研究

采用机械合金化法在煤焦油沥青碳质中间相中掺杂元素镍,借助X射线衍射仪和激光Raman光谱仪研究了掺杂元素前后中间相的结构变化,利用SRV高温摩擦磨损试验机考察了机械合金化法掺杂元素镍的碳质中间相作为润滑油添加剂的高温摩擦磨损性能.结果表明:机械合金化掺杂元素镍后,中间相的结晶有序度下降、微晶石墨平面尺寸减小,表明机械合金化掺杂镍促使中间相向无定形结构转变;碳质中间相作为添加剂具有高温减摩抗磨效应,与原始态或高能球磨处理的碳质中间相相比,采用掺杂镍的碳质中间相作为添加剂时,其高温减摩抗磨效应更为明显且持续时间更长;碳质中间相的高温减摩抗磨效应与高温摩擦机械作用诱发的平面石墨微晶尺寸增加幅度有关.

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.