有效应变指的是不可恢复的塑性应变？

weihua515

看一个文献，提到了有效应变，指的是不可恢复的塑性应变吗？
但是后处理中，塑性应变怎么判断呢？能直接读取？
比如我设定了某个塑性材料，定义了塑性阶段的应力-应变曲线
算出结果后，应力达到一个值，然后我从曲线中去找？

tonnyw

1# weihua515

Here is my understanding. In the real problem, the stresses and strains are multi-component. But what we have as input is only the stress-strain curve from unaxial tension test. How could we relate the multi-component stresses and strains to the 1D unaxial test? Therefore we need effective strains, such as effective plastic strain, effective total strain.

In postprocessing, you are supposed to have all these stuff which has nothing to do with stress-strain curve.

weihua515

但是有时候看到定义塑性材料时，输入的应力应变曲线怎么来的呢？

tonnyw

3# weihua515

As I mentioned in the previous message, it is from uniaxial tension test.

weihua515

但是除了单轴拉伸试验，没有其他材料的强度试验了吗？

zsq-w

但是除了单轴拉伸试验，没有其他材料的强度试验了吗？
weihua515 发表于 2011-7-17 17:45

这类测试，单轴拉伸试验比较好做、费用低，结果可靠性更好。

weihua515

6# zsq-w

恩，那我们目前拿到的一些材料应力应变曲线是怎么来的呢？
根据工程经验，大致给的？

zhangxd1985

有效应变是(2/3*eij*eij)^0.5