Friction and Wear Characteristics of Silicone-Modified Thermoplastics 760371
Self-lubricating plastic bearing materials can be produced by adding a small quantity of silicone fluid directly to the thermoplastic melt. The result is a substantial increase in the critical load-speed (limiting pressure-velocity or LPV) limit of the plastic, above which rapid wear takes place. The magnitude of the improvement in lubricity suggests the possibility of replacing metals with plastics, or replacing expensive plastics with silicone-modified, inexpensive plastics. LPV of some plastics has been raised as much as 1000 percent by the silicone additive, where LPV was measured at high speeds. At low speeds, less improvement is noted, but results are still significant.
Data on the effect of the additive on various thermoplastics will be presented, along with a discussion of the correlation between wear rate and LPV.
The additive also improves the handling properties of plastics, producing better flow, easier release from low-draft molds, and other advantages.