大量研究表明,在循环加载过程中材料的机械性能会产生变化,即:屈服段的消失,屈服极限的提高,材料初始塑性储备的降低,硬度的增加,脆性临界温度的升高和裂纹零件破坏强度的降低(这特别危险)。因此,对于在西伯利亚等北方条件下工作的旧零件蕴育着冬季产生破坏的危险性。对于铸钢零件应力集中区域的应力状态没有详细研究过,因此还弄不清楚在运用条 Numerous studies have shown that the mechanical properties of the material change during cyclic loading, ie, the failure of the yielding section, the increase of the yield point, the decrease of the initial plasticity of the material, the increase of the hardness, the increase of the critical temperature of the brittle fracture and the failure of the cracked part Decreased intensity (this is especially dangerous). As a result, old parts that work in northern conditions such as Siberia are at risk of damaging winter. The stress state of the stress concentration area of ​​the cast steel part has not been studied in detail,