压痕应变法应力计算函数和低合金钢力学性能的关系

Relationship between stress calculation function of indentation strain-gage and mechanical properties of low-alloy steel

关键词:  压痕应变法  应力计算函数  数值模拟  低合金钢  力学性能

Key words:  indentation strain-gage method  stress calculation function  numerical simulation  low-alloy steel  mechanical property

摘要:

压痕应变法是一种新型无损的应力检测方法，具有快捷方便、测试准确等优点，影响该方法测量精度的主要因素之一就是应力计算函数（压痕应变增量（Δε）与弹性应变（ε）之间的关系）的确定.文中在已有工作基础上，基于有限元数值模拟计算，结合试验标定结果，探讨了12种不同力学性能的低合金钢类材料应力计算函数的存在规律.结果表明，在获得材料拉伸力学性能的情况下，根据材料在零应力情况下的应变增量，可以获得该材料的应力计算函数，从而避免了应力计算函数确定时进行的复杂试验标定或模拟计算问题.

Abstract:

Indentation strain-gage method is one of basically non-destructive stress determination methods. It has some advantages, like quickness, convenience, accuracy and so on. One of the factors influencing the accuracy of stress measurement is determination of stress calculation function (the relationship between strain increment Δε and the elastic strain ε). Based on existing research, the relationship between stress calculation function and mechanical properties for 12 kinds of low-alloy steels was discussed in this paper. The numerical simulation method combined with experimental calibration results was adopted. The study shows that stress calculation function for a certain steel could be extracted if its mechanical properties and Δε₀ were obtained. By this way, the complex experimental calibration tests or numerical simulation works could be eliminated.