Friction and Wear of Solid-Lubricated Contact in Gas Turbine Engine Bearings

摘要

A study was performed for a high temperature solid lubricated ball bearing under conditions representative of a gas turbine engine. The performance predictions were compared to the experimental test behavior of complete ball bearings and showed good correlation. In the pin on disc type material sliding tests, the friction and wear performance of M-50, NC-132, and alpha silicon carbide pairs with HAC-1 type lubricant composite were determined. In the first test mode -- to simulate the interactions between the cage material and other bearing elements -- the pairing of HAC-1 with M-50 and NC-132 at conditions up to 30,000 rpm and 316 C showed that the HAC-1 and NC-132 pair gave the lowest friction and wear and more stable temperatures. In the second test mode--to simulate low speed skidding which occurs between the ball and race materials--rapid wear was found and friction was high. This test data was used to prepare traction coefficient models as input to the ADORE computer program for bearing performance simulation. The analysis predicted that due to the high traction coefficients, the interactive forces are quite large, erratic, and inducive to cage wear and breakage. The good agreement with full scale testing of bearings demonstrated the significance of this combined material evaluation computer modeling technique.