Abstract:
The rheological parameters of nine lubricating greases with different gelatinizer structure and seven lithium greases with different base oil viscosity and gelatinizer mass fraction were determined by means of HAAKE rheological instrument. The effects of gelatinizer structure and content, temperature, base oil viscosity and shear time on the rheological para meters were investigated. The comparison of thixotropy of the nine greases was made. The results showed that the strength limit decreases with the increase of temperature, but the plastic viscosity and the plastic index have no regular changes at all. With increase of the gelatinizer mass fraction and decrease of the base oil viscosity, the strength limit and the plastic viscosity of the grease, KG*2in which no additive is included, KG*2increased gradually but the plastic index decreased. Among the nine greases mentioned above, non soap grease such as polyurea grease and bentone grease has better thixotropic stability.