山形大学紀要（工学） 第11巻 第1号（1970）105-112
X-Ray Residual Stress and Hardness Measurement on Cold Rolled Gear
Kazuo INOUE and Seizo UEMATSU
There has been few systematic investigation made on the fatigue strength of cold rolled gear under practical conditions so far as we know.
The aim of this investigation is to study basic properties on the rolled gear.
X-ray stress measurement and observation on the structure of work hardened surface layer were performed.
The obtained results are as follows;
(1) Residual stress at the fillet of gear teeth is compressive stress, and its value is about - 2Okg/mm^2.
(2) In the case of non-pre-cut rolled gear, work hardened surface layer is about 0.4-0.6mm in depth, and the maximum value of hardness on the layer is VHN 250-350.
(3) The hardness and thickness of the layer has a tendency to vary along the gear tooth surface. The value at the pitch point is lower than one of the other position, and one at the fillet is the highest.
(4) According to the observation of microstructure and X-ray diffraction pattern, the texture in the surface layer is the fiber structure and crystals at the core of gear teeth are elongated to the radial direction.