微观组织及测量信号对超声横波评价材料硬度影响  

Microstructure and measurement signal influences based on ultrasonic shear wave for applied hardness determination

作　　者：门平 董世运[1] 程志远 康学良[1,4] 刘晓亭 Men Ping;Dong Shiyun;Cheng Zhiyuan;Kang Xueliang;Liu Xiaoting(National Key Laboratory for Remanufacturing,Academy of Army Armored Forces,Beijing 100072,China;92601 Troops,People＇s Liberation Army Navy,Zhanfiang 524009,China;Key Lab of Nondestructive Testing Ministry of Education,Nanchang Hangkong University,Nanchang 330063,China;College of Material Science and Engineering,Shanghai University,Shanghai 200444,China)

机构地区：[1]陆军装甲兵学院装备再制造技术国防科技重点实验室,北京100072 [2]中国人民解放军海军92601部队,湛江524009 [3]南昌航空大学无损检测技术教育部重点实验室,南昌330063 [4]上海大学材料科学与工程学院,上海200444

出　　处：《仪器仪表学报》2018年第9期146-155,共10页Chinese Journal of Scientific Instrument

基　　金：国家重点研发计划重点专项(2016YFB1100205);北京市科技专项(Z161100004916009);北京市科技计划(Z161100001516007)项目资助

摘　　要：硬度是材料力学性能的重要指标之一,采用超声无损检测方法评价材料硬度指标目前还存在诸多挑战。通过搭建高精度声时测量系统,采用横波直探头脉冲反射回波法测量不同热处理45钢试件厚度方向超声横波传播声时和底面反射回波幅值,分别计算横波声速和衰减系数;在测量超声横波声时,改变测量声时门信号的测量方式,研究不同微观组织及测量信号对超声横波声速的影响,通过构建材料硬度-微观组织-超声横波声速及衰减系数之间的映射关系,建立超声横波评价45钢试件硬度指标的标定模型,并对标定模型进行验证。研究表明,横波声速可以作为评价45钢试件硬度的评价参数,测量误差满足工程应用误差10%的要求;测量横波衰减系数与材料硬度之间的变化没有明显的映射关系,不能作为评价45钢试件硬度指标的评价参数。Hardness is one important parameter to assess the performance of mechanical materials.There are many challenges to evaluate the hardness by ultrasonic nondestructive testing methods. In this paper, the high-precision acoustic measurement system was built.The shear wave reflection echo amplitude and propagation time in the thickness direction of different heat treated 45 steel specimens are measured by pulse reflected echo method using shear wave straight probe.The shear wave attenuation coefficient and velocity are calculated respectively. The gate signalof measurement shear wave propagation time is also changed.Then, the effects of different microstructures and measuring signals for the shear wave velocity are studied by building mapping relationships of hardness, microstructure, ultrasonic shear wave velocity and attenuation coefficient. Besides, the calibration model for evaluating the hardness of 45 steel specimens by shear wave velocity is formulated.Experimental results show that shear wave velocity can be employed to evaluate the 45 steel specimen hardness and its measurement error can meet 10% requirementof the engineering application. There is no obvious mapping relationship between the shear wave attenuation coefficient and the hardness.Hence,the attenuation coefficient cannot be used as the evaluation parameter to evaluate the hardness of 45 steel specimen.

关 键 词：超声横波 硬度 微观组织 门信号 映射关系 

分 类 号：TG115.28[金属学及工艺—物理冶金] TH878[金属学及工艺—金属学]