Effects of Gear Depth and Carburized Part on Bending Fatigue Strength of Case-Carburized Spur Internal Gears

摘要

This paper presents a study on the residual stress and the bending fatigue strength of case-carburized spur internal gears. A heat conduction analysis and an elastic-plastic stress analysis during the case-carburizing process of the spur internal gear were carried out for various case-carburizing conditions by means of the case-carburizing simulator developed by the authors. Measurements of hardened layers and bending fatigue tests were carried out for different case-carburized spur internal gears. Effects of the case depth and the carburized part on the residual stress and the bending fatigue strength were determined. Furthermore, the relationship between the residual stress and the bending fatigue strength was examined.