奥氏体不锈钢预应变效果评价

PRE-STRAIN EFFECT EVALUATION OF AUSTENITIC STAINLESS STEEL

对奥氏体不锈钢进行预应变是为了获得良好的机械性能,预应变效果评价是改进钢材生产工艺的基础。应用概率论与数理统计知识,建立了预应变效果的评价体系:用F分布评价预应变对机械性能参数标准差的改变效果,用t分布评价预应变对机械性能参数均值的改变效果。以奥氏体不锈钢S30408的预应变效果评价为例,基于液氮温度下的有效拉伸试验数据,在双侧置信度为99%时,评价了S30408钢的9%预应变效果:(1) 9%预应变明显提高S30408钢屈服强度均值,其标准差基本不变;(2) 9%预应变对于S30408钢抗拉强度的均值与标准差基本无影响。

Pre-strain on austenitic stainless steel was a method in order to obtain good mechanical properties,the pre-strain effect evaluation was the basis of improving the production process of the steel. Applying the theory of probability and mathematical statistics,the evaluation system of pre-strain effect was established: the pre-strain effect on the mechanical properties parameter standard deviation was evaluated,using F-distribution;the pre-strain effect on the mechanical properties parameter mean value was evaluate,using t-distribution. For example of pre-strain effect on austenitic stainless steel S30408,based on the effective tensile test data at liquid nitrogen temperature,and the bilateral confidence was 99%,the effect of 9%-prestrain on the steel was evaluated: 1) 9%-pre-strain significantly increases the yield strength of steel S30408,and the standard deviation is basically unchanged;2) for steel S30408 tensile strength,9%-pre-strain is no effect on the mean and the standard deviation.