| 摘要 |
A method of forming a boss in a plate to be subject to cyclic fatigue loads is disclosed which addresses the problem of metal fatigue caused by punch forming bosses. The material of the plate is selected to have a high strain hardening coefficient in excess of 0.35. The boss is press formed 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 formula: radius = plate thickness X A where "A" has a value between 0.3 and 0.7 such that the arcuate portion of the boss work hardens under load to produce a region having a high local tensile strength. |
