温度-应力史对Q345钢力学性能影响的试验研究

An Experimental Study on Material Properties of Q345 Steel Impacted by Temperature-stress Process

为了对我国受火钢结构的承载力鉴定提供基础数据,利用微机控制电液伺服试验机及加温装置和变形测量装置,对我国某钢厂生产的钢结构用Q345(16Mn)钢,前期采用恒载升温试验方法对试件施加应力-温度作用,冷却后进行拉伸试验。试验结果表明:在300～600℃范围内,钢材前期所受温度对冷却后钢材的弹性模量和屈服强度基本没有影响;但钢材在经受温度时所施加的应力使钢材强度降低幅度均为20%左右。

In order to provide some basic datum for the bearing capability appraisal of a steel structure in fire, a computer control testing machine, a heating device and a deformation measuring appliance were used to do a series of tests on Q345 （16Mn） steel, In these tests, the method of transient tests were employed at first to impose a stress - temperature action on the test piece, and then tensile tests were made on these specimen after cooling. The results show that： between 300℃ and 600℃, there is little influence on the elastic modulus and yield strength of the steel acted by prophase heating; there is about 20% reduce on the strength of steel made by the stress acted during the stage of heating.