【摘要】 <正> 1.疲劳寿命估算方法概述 目前,工程中广泛采用的疲劳裂纹形成寿命估算方法主要有两种——名义应力法和局部应力-应变法。名义应力法利用所计算元件的名义应力历程和相应材料的光滑和缺口小试件的S-N曲线,通过线性累积损伤理论(Palmgren-Miner假设)计算疲劳损伤。名义应力法不考虑应力集中区进入塑性后的真实应力、应变状态,也不考考高、低峰值载荷对疲劳寿命更多还原

【Abstract】 In this paper,fatigue life prediction methods are briefly reviewed.The author supposes that the method based on energy criterion can get rid of the unreasonableness of Pa-lmgren-Miner hypothesis, so it is a good approach for fatigue life prediction and is worth while being further studied and applied. An example of fatigue life prediction for a centr-ically notched plate subjected to random loading based on kliman’s energy method has been given. The result shows that the predicted fatigue life using the energy method is better than the result predicted using local stress-strain method, and is in good agreement with previous test results of random loading.更多还原