S1160104 転勤疲労に伴う白色組織

Abstract

White etching area may be recoginized at the flaking part of a rolling bearing on which high contact stress of several GPa is applied repeatedly. Up to now, studies of white etching area of a ball has been less than studies of white etching area of inner and outer rings. In this study, as part of the flaking mechanism explication with white etching area of a ball, the form, the structure and chemical composition of white etching area were investigated. The form of the white etching area of a ball is identical with the form of the white etching area of the inner ring and the outer ring mostly. The white etching area of the ball is almost formed from the ferrite of tens of nm and is almost identical with the white etching area of inner and outer rings. The carbon density of white etching area is higher than the carbon density of the matrix, and much carbon exists at the grain boundary of the ferrite of tens of nm.