Effect of Nonmetallic Inclusions on Rolling-Contact Fatigue Life in Bearing Steels
SourceRolling-contact fatigue life tests were studied to evaluate the effect of nonmetallic inclusions in bearing steels similar to AISI 52100.
Fatigue tests were conducted on a test machine that was composed of a round disk specimen substituted for the housing washer of a thrust ball bearing. The specimen was loaded at 455 and 500 kg/mm2 (4.46 × 109 and 4.90 × 109 N/m2) in maximum hertzian stress, lubricated with spindle oil, and operated at room temperature.
The results of the fatigue tests showed that alumina-type inclusions were very harmful to fatigue life, but sulfide inclusions not only had no influence but increased the fatigue life in air-melted and even vacuum-melted steels. In electro-slag remelting steel, increased fatigue life indicated the possibility of effects with the exception of nonmetallic inclusions.