Development of Tribological Test Equipment and Measurement of Galling Resistance of Various Grades of Stainless Steel

A mechanized galling tester has been developed to evaluate the galling resistance of material pairs at room temperature (RT) as well as at elevated temperature condition. The test rig has a facility for online measurement of frictional torque during the test which is useful in assessing the incipient scoring. Both the test rig and the test method conform to the recent ASTM G196-08 standard. Galling resistance of two different grades of stainless steel SS 304 and 304 L has been evaluated in self-mated condition at RT and elevated temperature (300 °C). The parameter called galling₅₀ has been reported for the materials tested. The galled surface indicated the severe plastic deformation in the direction of sliding and it is dominated by the typical adhesive wear mechanism. The recent ASTM G196-08 test method for measurement of galling resistance of material pairs appears to be superior to an older ASTM G98 because galling behavior was prevailed by the stochastic wear phenomenon.