聚氨酯夹芯板发泡缺陷电磁超声导波快速检测  

Rapid detection of foaming defects of polyurethane sandwich insulation board using electromagnetic ultrasonic guided waves

作　　者：屠泽熹 涂君[1,2] 袁宁 张旭 宋小春 Tu Zexi;Tu Jun;Yuan Ning;Zhang Xu;Song Xiaochun(School of Mechanical Engineering,Hubei University of Technology,Wuhan 430068,China;Hubei Province Key Laboratory of Modern Manufacture Quality Engineering,Wuhan 430068,China;Technology Research Institute,CRRC Changjiang Group Science and Technology Development Branch,Wuhan 430212,China)

机构地区：[1]湖北工业大学机械工程学院,武汉430068 [2]现代制造质量工程湖北省重点实验室,武汉430068 [3]中车长江集团科技开发分公司工艺研究所,武汉430212

出　　处：《仪器仪表学报》2021年第5期270-279,共10页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金(51707058,51807052);湖北省自然科学基金(2019CFA021)项目资助。

摘　　要：聚氨酯夹芯板在生产中因发泡不均容易在聚氨酯泡沫层形成空洞型缺陷,直接影响其保温效果,为此提出了一种从金属板外侧实施的电磁超声SH导波检测的快速检测方法。通过理论分析、解析推导、仿真计算和试验验证,建立了聚氨酯夹芯板中的SH导波透反射比系数与激励参数之间的关系,结果表明,当磁铁间距为4.5 mm时,控制SH0导波入射角度为75°,能够得到最佳的检测效果。同时也进一步验证了SH0导波接收信号幅值与缺陷面积、缺陷深度均基本上呈线性关系。在此基础上,提出了一种可应用于实际检测的缺陷当量大小评价方法。通过评价公式进行修正,可消除因收、发探头之间距离变化引起的缺陷信号评价波动问题,这对于后期实现缺陷定位具有较好的指导作用。In the production of polyurethane sandwich insulation board,void defects are easy to form in the polyurethane foam layer due to uneven foaming,and it directly affects the heat conservation effect.For this reason,a rapid detection method implementing electromagnetic ultrasonic SH guided wave inspection from the outside of the metal board is proposed.Through theoretical analysis,analytical derivation,simulation calculation and experiment verification,the relationship between the transmission reflection coefficient ratio of the SH guided wave in polyurethane sandwich insulation board and the excitation parameters is established.It is found that when the magnet spacing is 4.5 mm and the incident angle of the SH0 guided wave is about 75°,the best detection effect can be achieved.Furtherly,it is verified that the amplitude of the received signal of the SH0 guided wave has linear relationship with both the defect area and defect depth basically.On this basis,a defect equivalent size evaluation method that could be applied in actual inspection is proposed.With the evaluation formula,the problem of defect signal evaluation fluctuation caused by the change of the distance between the receiving and transmitting probes can be eliminated,which has a good instruction for the later realization of defect location.

关 键 词：电磁超声 SH导波 聚氨酯夹芯板 透反射系数 

分 类 号：TH165.4[机械工程—机械制造及自动化] TB553[理学—物理]