基于石蜡基油的锂基润滑脂流变性研究

摘要

以12-羟基硬脂酸锂皂稠化剂和矿物润滑基础油制备了锂基润滑脂。考察了基础油黏度、稠化剂含量及温度对锂基润滑脂的触变性、储存模量、应变幅度和表观黏度等流变学参数的影响，并对其影响机理进行了探讨。结果表明：基础油黏度增大，屈服应力先增大后减小，而表观黏度增大，400SN 的锂基润滑脂结构恢复最慢；皂含量增加，锂基润滑脂的屈服应力和表观黏度增大，结构恢复变慢；锂基润滑脂具有线性黏弹区，超过其屈服应力后，出现明显的剪切变稀，达到流动点，表现出黏性流体性质。%In order to study the rheological properties of lithium lubricating grease systematically, the lithium lubricating greases were prepared using 1 2-hydroxy stearic acid lithium soap thickener and mineral lubricating base oil.The influence of base oil viscosity,thickening agent dosage and tempera-ture on the thixotropy of lithium base grease,storage modulus,strain amplitude,the apparent viscosi-ty,and the corresponding mechanisms were examined.The results show that with increase of soap con-tent in lithium lubricating grease,the apparent viscosity increases while the yield stress shows the tend-ency of lowered after first increase.The 400SN lithium grease is the slowest one to restore its original structure,and that the yield stress and apparent viscosity increase with the soap dosage increasing, while the structure recovery rate decreases.Lithium grease possesses a linear sticky play area.Beyond the yield stress,the shear thinning appears.At the flow pour point,the grease shows its viscous flow properties.