That property of lubricating grease which is observed when a small separate portion of it is pressed together and then slowly drawn apart. Texture should be described in the following terms:
Brittle â€“ Has a tendency to rupture or crumble when compressed
Buttery â€“ Separates in short peaks with no visible fibers.
Long Fibers â€“ Shows tendency to stretch or string out into a single bundle of fibers.
Resilient â€“ Capable of withstanding moderate compression without permanent deformation or rupture.
Short Fibers â€“ Shows short break-off with evidence of fibers.
Stringy â€“ Shows tendency to stretch or string out into long fine threads, but with no visible evidence of fiber structure.
Tacky â€“ The property of adhesiveness, especially to metal surfaces. Greases containing polymers tend to be tacky.
Other terms, such as Smooth, Rough, Grainy, etc., are defined under Bulk Appearance.
The solid particles which are relatively uniformly dispersed in a liquid lubricant to form the structure of lubricating grease. The solid particles may be fibers, as is the case with various metallic soaps, or plates or spheres, as is the case with some of the non-soap thickeners. The general requirements are that the particles can be dispersed uniformly in the liquid lubricant where they interact to form a stable structure.
Decrease in grease consistency (softening) as a result of shearing, followed by an increase in consistency (hardening) after shearing is stopped. (Thixotropic age hardening is a relatively prolonged process proportional to aging time and is seldom, if ever, complete. In contrast, the apparent viscosity increase in non-Newtonian systems with decreasing shear rate is instantaneous and fully reversible. Lubricating grease is both thixotropic and non-Newtonian.)
See OK Load