摘要
分析了表面波引起的结构钢非线性塑性响应性能,构建得到应力应变、塑性损伤与超声非线性系数的相互作用关系,实现对材料力学特性与使用寿命进行评估的过程。通过CMT-5205微机实现电子万能拉伸机的运动控制,将加载到不同应变程度的标准试件进行卸载后再对其实施非线性电磁超声测试。研究结果表明:应变达到7%以下试件塑性损伤程度提高后,形成了更大幅度的二次谐波,应变达到7%以上试件发生了二次谐波幅的显著减小。试件不同应变程度的塑性损伤后,形成了比未塑性损伤试件更大的二次谐波变化幅度。提高塑性损伤程度后,材料受到超声波后发生了非线性应力应变,引起更明显的超声波畸变。应变达到7%以上时,材料发生了颈缩,结构钢试件应力也发生了减小。
The nonlinear plastic response of structural steel induced by surface wave was analyzed,and the interaction relationship between stress strain,plastic damage and ultrasonic nonlinear coefficient was established to evaluate the mechanical properties and service life of material.The CMT-5205 microcomputer was used to realize the motion control of electronic universal stretching machine.After unloading the standard specimens loaded with different strain levels,the nonlinear electromagnetic ultrasonic testing was carried out on them.The experimental results show that when the strain is below 7%,the plastic damage degree of specimen is improved,and the second harmonic amplitude of specimen is significantly reduced when the strain is above 7%.After the plastic damage of different strain degree,the second harmonic of specimen is larger than that of specimen without plastic damage.When the degree of plastic damage is increased,the nonlinear stress and strain occur after the material is subjected to ultrasonic wave,which leads to more obvious ultrasonic distortion.When the strain reaches more than 7%,the material is necked and the stress of structural steel specimens is reduced.
作者
张志辉
李峰
ZHANG Zhihui;LI Feng(Group Technology Department,Zhengzhou Tengfei Construction Engineering Group Co.,Ltd.,Zhengzhou 450047,Henan,China;College of Materials Science and Engineering,Henan Polytechnic University,Zhengzhou 451460,Henan,China)
出处
《中国工程机械学报》
北大核心
2022年第1期86-90,共5页
Chinese Journal of Construction Machinery
基金
河南省科技攻关项目(172102210094)。
关键词
塑性变形
电磁超声
损伤检测
结构钢
二次谐波
plastic deformation
electromagnetic ultrasound
damage detection
titanium alloy
second harmonic
