| 摘要 |
A method is provided to form a boss in a plate such as a bearing retaining plate which will be subject to cyclic fatigue loads. Such loads occur for example when used in a compact vehicular gearbox housing. The method comprises selecting the material of the plate to have a high strain hardening coefficient in excess of 0.35 such as austenitic stainless steel Grade 304 and press forming the boss against a die such that the radius of curvature of the region between the original plate and the wall of the boss complies with the following formula: radius = plate thickness x A In the formula "A" is a value between 0.3 and 0.7. By using the method, the arcuate portion of the boss work hardens under load to produce a region having a high local tensile strength. |
