1961 Volume 27 Issue 313 Pages 113-118
One of troublesome problems of ball and roller bearings, especially of roll neck bearings, is appearance of the smearing crack which is often observed on smeared surfaces of the bearing races.
Some metallurgical observations on the cracked part of the race showed that the structure of the surface layer at the region near the crack was changed from the normally quenched and tempered structure, and that sliding contact between a race and mating part, accompanied with high frictional heating, was likely to cause appearance of the crack and change of the metallurgical structure.
Then the sliding contact under high pressure-sliding between SKH 2 and SUJ 2 (JIS) test pieces-was analysed experimentally, especially on the interface temperature of the contact. The interface temperatures of about 1200°C high were measured in the sliding of a second Under the conditions of sliding velocity 119 cm/sec., contact area 2. 0 or 1. 4cm22and contact load 175-340 kg.
And on stop of the sliding, the interface temperature dropped so quickly as to harden the steel structure.
