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目的 研究非均匀亲和性界面对流体动压条件下润滑油膜厚度的影响.方法 通过对固体试样表面进行张力修饰以获得对润滑液体不同的亲和性,其中包括表面的不同部分对液体的亲和性不同,即非匀质亲和性表面.试验中利用防指纹油液(AF)对普通钢滑块进行张力修饰得到了匀质AF滑块和非均匀性AF滑块,测量了钢滑块、入口AF滑块、出口AF滑块和全表面AF滑块的油膜厚度随倾角的变化,同时利用防指纹油液对阶梯滑块进行张力修饰得到了AF阶梯滑块,测量了阶梯滑块和AF阶梯滑块在倾角为1:2231和平行间隙两种条件下的油膜厚度随速度的变化.结果 四种滑块的油膜厚度随倾角的增大均呈现先增大后减小的趋势,存在最佳倾角,且普通钢滑块表面、非均匀亲和性AF表面、均匀AF表面的油膜厚度依次降低.对阶梯滑块和AF阶梯滑块的测量结果表明,AF阶梯滑块产生的油膜厚度一直低于阶梯滑块.结论 在流体动压薄膜润滑条件下,固液界面亲和性可以对膜厚产生明显的影响.通过选择性修饰试样表面,使得表面润湿性具有区域性差异,油膜厚度降低,认为造成该现象的原因是润滑剂在固液界面亲和性低的部分发生较强的侧泄.

The work aims to investigate effects of heterogeneous affinity interface on hydrodynamic lubricant film thickness at hydrodynamic pressure. Tensional modification was performed to obtain interfaces of different affinities, including different parts on surfaces of different heterogeneous affinities, i.e., non-homogeneous affinity surface. Homogeneous AF slider and non-homogeneous AF slider were obtained by modifying plain steel slider with anti-finger-print oil (AF). Variation of film thickness with inclination was measured for steel slider, inlet-AF slider, outlet-AF slider and whole-surface AF slider. Mean-while, homogeneous AF stair slider was obtained by modifying stair slider with anti-finger-print oil (AF), and variation of film thickness with speed was measured for step-1.5 slider and AF step-1.5 slider under provided withθ =0 andθ= 1:2231, respec-tively. Film thickness of four slider increased first and then decreased with the increase of inclination, optimum inclination ex-isted. And film thickness of steel slider, heterogeneous affinity slider and AF slider decreased in sequence. Besides, film thick-ness of AF step-1.5 slider was always lower than that of step-1.5 slider.Provided with film lubrication at hydrodynamic pres-sure, affinity of the solid/liquid interface can obviously influence film thickness. Selective modification of sample surface can endow surface wettability with regional difference and induce low film thickness, which is attributed to the side leakage in parts of lower affinity despite of the slippage step effect.