无硫磷有机钼对不同基体材料的润滑效果研究

将不同添加量的无硫磷有机钼添加剂加入柴油机油中，利用SRV摩擦磨损试验机考察其在不同添加量下对45号钢和GCr15钢的减摩抗磨性能；采用电子扫描电镜（SEM）、X射线能谱仪（EDS）、光电子能谱（XPS）分析磨痕的表面形貌、元素组成及价态。结果表明：无硫磷有机钼在45号钢上的减摩性能随添加量的增大而提高，但抗磨性能降低，当添加量超过0.6%时，磨损体积甚至超过不添加无硫磷有机钼时的磨损体积；无硫磷有机钼在GCr15钢上的润滑效果远好于在45号钢上的润滑效果，且试验的摩擦因数和磨损体积均随添加剂添加量的增加而减小。添加无硫磷有机钼后,在摩擦过程中基体表面能够附着含铁和钼氧化物的边界润滑膜,起到润滑作用，但过量的无硫磷有机钼在45号钢表面形成MoO3磨粒,增大磨损体积，并导致基体表面氧化严重，发生严重磨损，加剧了磨损体积增大的趋势；而GCr15钢的硬度大，因此不会出现磨损体积增大的情况，无硫磷有机钼能够有效地起到抗磨作用。

LUBRICATING EFFECT OF SULFUR-AND PHOSPHORUS-FREE ORGANIC MOLYBDENUM ON DIFFERENT MATRIX MATERIALS

Different amounts of sulfur- and phosphorus-free organic molybdenum (SPFOM) additive were added into diesel engine oil to measure the friction reduction and anti-wear properties of SPFOM on No.45 steel and GCr15 steel using SRV friction wear machine. Scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) were employed to analyze the worn surface morphologies, elements with various valences. The test results show that the friction reduction property of SPFOM on No. 45 steel is improved with increasing additive amount, but the anti-wear property declines, and the wear volume is even larger than that of diesel engine oil without SPFOM when the additive amount is above 0.6%; the lubricating effect of SPFOM is much better on GCr15 steel than that on No. 45 steel, and both friction coefficient and wear volume decrease with the increasing of additive amount. Boundary lubricating film containing molybdenum and ferrous oxide is formed on the matrix surface during friction process with SPFOM in the oils, but too much SPFOM forms MoO3 particles, which increase wear volume of No. 45 steel, serious oxidation of the matrix surface, and wear trend. While the hardness of GCr15 steel is high enough to avoid the increase of wear volume, resulting in effective anti-wear for lubricating oil with SPFOM.