Scoring Resistance of Spur Gears with Various Coatings : 2nd Report, Scoring Tests under Dry Friction

Abstract

To examine the scoring resistance of spur gears with various coatings under dry friction, scoring tests on gear pairs coated with copper, graphite, zinc, molybdenum disulfide and phosphate were carried out under dry friction using a power-circulating gear machine. Further, variation in the bulk-temperature of the gear tooth was measured by a thermocouple embedded in the side of the tooth. From the experimental results a significant effect of copper and graphite on the scoring resistance under dry friction was recognized. The bulk-temperature of the gear tooth dropped after the initial stage of scoring for all gear pairs.