蠕变寿命外推的能量模型

ENERGY MODEL OF CREEP LIFE EXTRAPOLATION

根据熵守恒定律和能量守恒定律,推导出一种新的蠕变寿命预测能量模型。单位体积外载荷所作机械功Wc=σε与时间t的幂函数之积为常数,即Wctp=B(p和B为常数)。对现有2.25Cr-1Mo钢和1Cr-0.5Mo钢的试验数据分析、研究,发现能很好满足该模型。为由短期蠕变数据预测长期蠕变寿命提供一种新方法。

For structural and machine components in service at high temperature and pressure,creep life assessment is a major concern because of safety and economic reasons.In order to solve the problem,a new energy model for creep life prediction is derived from laws of entropy conservation and energy conservation.The work of creep defined as Wc = σε is found to vary with time t and temperature T（in particular Wc t p = B,where p and B are constants）.This function moreover,owing to its simple expression,it is very easy to use this model to predict the creep life.To check the validity of the new model,the published data of 2.25Cr-1Mo and 1Cr-0.5Mo steel have been studied and analysed.A good coincident is noted between the model and the results.The new method can be used for long creep life to require extrapolation of shorter time test results.