Will the presence of contaminants affect the fit of the ball and raceway in a ball bearing?

Ball bearings are made of hardened steel, but there is a very high contact pressure in the small contact area between their rolling elements and raceways. In angular contact ball bearings, the pressure between the ball and the seat ring is very high, and this high-pressure state makes the bearing very susceptible to contamination. When pollutant particles enter the interior of the bearing and roll between the rolling elements and the raceway, they will leave indentations on the raceway or rolling element surface. These indentations will damage the originally smooth rolling surface and raceway surface, causing pits (plastic deformation).
Specifically, soft contaminants such as polymer particles or metal shavings can leave soft edged indentations on bearing rolling elements or raceways, while hard contaminants such as sand particles or metal fragments can produce smaller but sharper indentations. These indentations will cause an increase in contact pressure at the edges of the indentations each time the rolling elements pass by, resulting in higher stress and a shortened fatigue life of the bearing. In addition, pollution particles can also cause wear on the surface of bearings, especially in the sliding parts between rolling elements and raceways. This kind of wear will further exacerbate the deterioration of the bearing, reducing its matching degree and service life.