在拉伸载荷下铁素体球墨铸铁损伤力学特性

Study on the Characteristics of Damage Mechanics of Ferrite Ductile Cast Iron under Tensile Loading

根据损伤力学的基本原理，利用测量电阻的方法，研究了拉伸受力状态下铁素体球墨铸铁的损伤力学特性．研究结果表明，当应力大于一定值时损伤发生，且随应力增加而逐渐增大，并得出了损伤变量随应力而变化的数学模型．铁素体球墨铸铁的损伤阈值低于屈服强度．损伤阈值随球化率而增大，但临界损伤变量与球化率的关系不大，在本试验条件下，约为０．０６～０．０６８．

According to principle of damage mechanics, the damage characteristics of ferrite nodular cast iron under the condition of uniaxial stress have been studied by means of measuring electricity. The results showed that the damage in nodular cast iron happens when the applied stress is more than a fixed value, and the damage variable increases with stress. The mathematical model of admage variable as a function of stress was obtained. The damage threshold in nodular cast iron is below the yield strength and increases with nodularity. The critical damage variable is not related to the nodularity, which is about 0.06- 0.068.