IN 738LC材料Chaboche热粘塑性本构模型的隐式Euler格式

为了提高Chaboche模型的数值积分效率,推导了该模型的Euler隐式积分格式,针对IN738LC材料,将该积分格式编写成FORTRAN程序,利用通用有限元分析软件Marc的用户子程序接口HYPELA2,将该隐式积分格式与有限单元法结合起来.对实验进行了数值模拟,并将隐式算法和显式算法与实验结果作了对比,结果发现隐式算法是合理的,比显式算法收敛性要好.

Implicit Euler Form of Chaboche Thermal Viscoplastic Model of IN738LC Material

In order to improve the efficiency of numeric integral of Chaboche constitutive model,backward Euler integration method,which also called implicit Euler integration method,of Chaboche model was brought forward.As an example,material IN738LC was used.Based on the backward Euler integration equation,FORTRAN programming format was used.Such a program was linked with FEM by user's program interface HYPELA2 in MSC.Marc of a general FEM software.As a result,backward Euler method applied to Chaboche model could be used for structural analysis.A numerical result was given.Comparison was made between the numerical result and the experimental one.Comparison between the result of backward Euler method and the one of forward Euler method was made,too.It is found that the backward Euler method is accurate and has better convergency than the forward one.