锂基润滑脂屈服应力测定方法的探讨

A Study for Determining the Yield Stress of Lithium Lubricating Grease

选用旋转流变仪测定了锂基润滑脂的屈服应力。根据锂基润滑脂的流变性质,采用稳态、瞬态和动态实验等方法测定了屈服应力值。实验结果表明,不同测定方法对屈服应力值的影响较大,稳态、瞬态和动态实验测得的屈服应力值依次逐渐增大;稳态和动态实验的测定值为确定的值,而瞬态实验得到的应力值为一个范围。

Rotated rheometer was used to determine the yield stress of lithium lubricating grease. Based on the rheological behaviour of lithium lubricating grease, the steady-state, transient-state and dynamic-state flow experiments were selected to obtain yield stress value. According to the measurement results, different ways can effect yield stress values efficiently, and the steady-state, transient-state and dynamic-state flow results are rised in sequence. The results measured by steady-state and dynamic-state flow experiments are a single value, but the result measured by transient-state flow experiment is in a range.