介绍可早期检测铁磁试件应力集中状况和疲劳损伤程度的无损检测金属磁记忆方法,通过对45钢中心裂纹试样进行拉伸疲劳试验,测定了磁信号特征参量随循环次数N的变化关系,研究了磁信号特征参量在疲劳裂纹扩展过程中的变化规律,分析了以磁记忆特征参量评价试件疲劳损伤程度的可行性.以磁性特征参量为基础,定义并建立了新的疲劳损伤参量模型,以新定义的损伤参量来表示试件的损伤程度更加清晰,具有更好的可操作性.%The paper introduces a metal magnetic memory method for early detecting any stress concentration condition and fatigue damage of ferromagnetic test-pieces. Through the tensile fatigue test for No. 45 steel test-piece with central cracks, the characteristic parameter of magnetic signals changing with the cycle N is measured, with research on the rule of characteristic parameter changing with propagation of fatigue cracks, and analysis for the feasibility of evaluating the fatigue damage of test-pieces through such magnetic memory characteristic parameter. With the magnetic parameter as the basis , a new parameter model of fatigue damage is defined and established, which is more explicit and operable to indicate the damage degree of test-pieces.
展开▼
