圆棒拉伸试样蠕变过程中的应力应变分布分析

A study of the creep stress and strain characteristics of smooth and notched bars

对光滑及切口圆棒试样进行有限元蠕变分析,得到了蠕变过程时的应力应变分布。在相同的平均净拉伸蠕变应力下,切口的存在使得最小截面上的平均Mises应力和平均轴向应力小于光滑试样。切口还导致蠕变时的应力松弛并使得试样的最大应力不再发生在切口根部。这可以用来简单解释切口对试样断裂寿命的影响。

The creep stress and strain characteristics of smooth and notched bars are analyzed in the paper. Under net average tensile applied stress, the existence of notches (V-type and U-type) decreases the average Mises stress and axial stress along the minimum sections. Depending on the types of the notches, the maximum stress is not at the tip of notches, since there is creep relaxation in the high stress places.