静态热老化对润滑脂皂纤维缠结及恢复性能的影响∗

摘要

The thermal ageing properties of lubricating greases were simulated under limited operating temperature of 150 ℃ and by using static thermal ageing method.The effect of aged time on fibrous entanglement,shear property and re-versibility of lubricating greases was carried out by using rheological method. It is found that the fibrous entanglement of aged grease samples is decreased with the increasing of aged time at first and then increased,and the variation of apparent viscosity under continues shear condition displays the similar tendency.Compared with the new grease samples,the lubrica-ting grease samples after being aged are hardened and the reversibility is gradually decreased as well.%采用静态热老化方法模拟锂基润滑脂承在极限使用温度(150℃)下的热老化行为，利用流变学手段探究老化时间对润滑脂皂纤维缠结程度、剪切性能以及结构恢复性能的影响规律。研究结果表明：润滑脂在极限工作温度下热老化后，皂纤维缠结程度出现了先减小后增加的趋势，连续剪切下的表观黏度展现出相似的规律；相较于新润滑脂样品，热老化后的润滑脂样品出现了硬化，使得润滑脂样品的恢复性能逐渐变差。