Q460高强钢单调与反复加载性能试验研究

Experimental study on material properties of Q460 high strength steel under monotonic and cyclic loading

通过对Q460高强钢进行单向拉伸与反复加载下材料性能试验,得到了各试件单调拉伸和反复加载下的应力-应变关系曲线,以及反复加载下的骨架曲线,并将试验结果与文献研究结果进行了对比。试验结果表明:单向拉伸材性试验中,11 mm厚Q460C高强钢板的平均断后伸长率为23.7%,屈强比为0.847;21 mm厚钢板的平均断后伸长率为30.4%,屈强比为0.792;Q460钢的循环硬化程度比Q345钢明显减弱,主要原因是随着钢材强度的提高,钢材的屈强比增大,钢材的应变强化效应减小。根据钢材反复加载的滞回曲线,提出了Q460高强钢材的应力-应变滞回模型,用该模型计算得到的关系曲线与试验曲线对比,两者吻合较好。

By experimental study on the material properties of Q460 HSS under both monotonic and cyclic loading,Monotonic compressive loading and hysteretic curves of Q460 steel were obtained.The cyclic skeleton curves were compared with the existing research work.Results of the test show that,under monotonic loading,the average elongation rate of Q460C HSS plate with the thickness 11mm is 23.7%,and the average yield to tensile strength ratio is 0.847,while the average elongation rate of Q460 HSS plate with the thickness 21mm is 30.4%,and the average yield to tensile strength ratio is 0.792.The cyclic hardening property of Q345 is more obvious than that of Q460,since the increase of the strength of steel results in increased yield ratio while reduced strain hardening effect.By the hysteresis curve of Q460 obtained under cyclic loading,the stress-strain hysteresis model of Q460 HSS was proposed,which matched very well with experimental curves.