非皂基高温功能润滑脂摩擦学性能

Tribological properties of non-soap base high temperature functional grease

将天然硅酸盐矿物凹凸棒石粉体,分别经硅烷偶联剂KH-550和阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)表面有机改性,在粉体表面成功接枝有机基团。以有机改性后的凹凸棒石粉体作为稠化剂,制备出滴点高于280℃的不同稠度标号的高温润滑脂。用国标和行业标准考察了各脂样的技术指标。采用德国Optimal SRV-Ⅳ摩擦磨损实验机评价各脂样在定载变速和定速变载条件下的摩擦学性能,借助SEM、EDS和XPS对摩擦副表面进行了分析测试。结果表明,各脂样的技术指标均符合国标和行业标准对润滑脂性能的要求,且具有优良的极压性;KH-550改性的凹凸棒石所制备的脂样的摩擦学性能受载荷和速度的影响较大,整体低于CTAB改性凹凸棒石所制备的脂样;以凹凸棒石为稠化剂制备的高温润滑脂在润滑过程中,具有在摩擦表面形成修复层的功能。

The natural silicate mineral attapulgite powders were modified respectively by a silane coupling agent KH-550 and cationic surface active agent cetyltrimethyl ammonium bromide (CTAB).Then the powder surface successfully connected branches organic group.With organic modified attapulgite powders as a thickening agent,the different labels high temperature greases were prepared,which had the dropping point above 280℃.The technical indicators of various grease samples were investigated with GB and industry standards.The German Optimal SRV-Ⅳ friction and wear machine was used to evaluate the tribological properties of grease samples under the given load variable speed and constant speed variable load conditions.And SEM,EDS and XPS were used to analyze the friction surface.The results showed that:each grease sample’s technical indica-tors are in line with national standards and industry standards for grease performance requirements,and greases have excellent extreme pressure;the load and speed affect the tribological properties of grease samples made of KH-550 modified attapulgite very much,tribological properties of which are lower than the overall samples which were prepared by CTAB modified attapulgite powders;the high-temperature grease,whose thickener was organic attapulgite powders,has a forming repairing layer on the friction surface function in lubrication process.