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 have 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, internal residual stress distributions of ball by using high energy white X-ray of SPring-8 (A method) and laboratorial X-ray measurement equipment (B method) were investigated. The former was moddified by surface residual stress accoding to B method. The latter was modified by releasing stress in the form of electrolytic polishing. The results showed modified residual stress distributions almost agree qualitatively.
