当材料弹塑性变形时在低循环范围内材料的寿命主要试验方法,取决于应力一变形和极限状态,其特性被材料的性能和加荷条件限定。当低循环疲劳试验时可由两个主要加荷方式来区别:刚性的(恒定变形振幅,△ε=Const)和柔性的(恒定负荷或应力振幅,Sa=Const)。试验过程中变形图表的变化特性和它们的柔性加荷和刚性加荷状态的特性参数存在着差别。在刚性状态中负荷使弹性和塑性组合间变形的重新分布。此时,由于后者在全 The main test method for the life of a material in the low-cycle range when the material is elastically deformable depends on the stress-strain and the ultimate state, the properties of which are defined by the properties and loading conditions of the material. When low cycle fatigue test can be distinguished by two main load: rigid (constant deformation amplitude, △ ε = Const) and flexible (constant load or stress amplitude, Sa = Const). The variation characteristics of the deformation charts during the test differ from the characteristic parameters of their flexible and rigid loading states. In the rigid state, the load redistributes the elastic and plastic combinations. At this point, because the latter is in full