基于弹性计算的铝合金活塞低循环疲劳寿命预测

Forecast of Low Cycle Fatigue Life for the Aluminium Alloy Piston Based on the Elastic Calculation

为了研究内燃机铝合金活塞在高温蠕变影响下的低循环疲劳寿命，以柴油机铝合金活塞弹性有限元计算所得到的名义应力、应变为基础，利用Neuber原则计算其真实弹塑性应力应变．根据活塞载荷的特点进行了高温蠕变影响下的低循环疲劳寿命预测公式的理论推导，提出了一组预测铝合金活塞低循环疲劳寿命的公式，并对公式的工程应用价值进行了试验验证．

To study the low cycle fatigue life of the ICE aluminium alloy piston under the influence of high temperature creep, based on the result of elastic finite element calculating and by means of the Neuber principle for the part nominal stress-strain analysis, the elastic and plastic strain of the aluminium alloy piston on the diesel engine was calculated. According to the loading characteristic of ICE piston, the forecasting formulae of its low cycle fatigue life was derived under the influence of high temperature creep. A set of forecasting formulae concerning the low cycle fatigue life of piston was put forward and also confirmed with the experiment.