低合金高强钢的疲劳断裂行为研究

Study on fatigue fracture behavior of low alloy high strength steel

为研究低合金高强钢的断裂机理,以260LAD、340LAD、420LAD材料为例,在高温、低温、酸性腐蚀条件下用万能试验机测试其应力比为0.3、1.0时的疲劳性能。结果表明:高温、低温都会导致试样的应力幅值降低,但在0、600℃下,试样的抗疲劳性能较好;酸性腐蚀溶液对试样影响较大,易疲劳断裂;在pH值为7时,试样的应力幅值较高,抗疲劳性能较好,不会发生严重断裂;其中420LAD的抗疲劳性能最高。

In order to study the fracture mechanism of low alloy high strength steel,260LAD,340LAD and 420LAD materials were taken as examples.The fatigue properties of the three materials were tested by universal testing machine under the conditions of high temperature,low temperature and acid corrosion with the stress ratio of 0.3 and 1.The results show that the stress amplitude of the sample decreases at both high and low temperature,but the fatigue resistance of the sample is better at 0℃and 600℃.Acid corrosion solution has great influence on the sample and is easy to fatigue fracture.When pH value is 7,the stress amplitude of the sample is higher,the fatigue resistance is better,and the serious fracture will not occur.Among them,the 420LAD has the highest fatigue resistance.