基于激光超声在高温下对超声波声速的数值模拟  

Numerical simulation of ultrasonic velocity at high temperature based on laser ultrasonic

作　　者：陶程 殷安民[1,2] 应志奇 王煜帆 郭智敏 TAOCheng;YINAn-min;YINGZhi- qi;WANGYu-fan;GUOZhi-min(Faculty of Mechanical Engineering ＆ Mechanics,Ningbo University,Ningbo 315211,China;Part Rolling Key Laboratory of Zhejiang Province,Ningbo 315211,China;Ningbo Branch of Chinese Academy of Ordnance Science,Ningbo 315103,China)

机构地区：[1]宁波大学机械工程与力学学院,浙江宁波315211 [2]浙江省零件轧制成形技术研究重点实验室,浙江宁波315211 [3]中国兵器科学研究院宁波分院,浙江宁波315103

出　　处：《激光与红外》2018年第7期815-820,共6页Laser & Infrared

基　　金：浙江省自然科学基金项目(No.Q17E050012);宁波市自然科学基金项目(No.2016A610057)资助

摘　　要：超声波声速对于缺陷检测和材料特性表征有着直接影响,因此,研究不同温度下声速的变化规律十分重要。本文通过有限元法对不同温度下激光点源激发的纵波、横波、声表面波的传播速度进行了数值模拟,并得到纵波、横波、声表面波声速与温度的关系式。根据所得到的表达式,反推出了在高温下的泊松比与弹性模量。结果表明:纵波、横波、声表面波声速随温度升高呈现线性降低关系,且随温度的变化率分别为0.8374 m·s^(-1)·℃-1、1.203 m·s^(-1)·℃^(-1)、1.096 m·s^(-1)·℃^(-1)。根据所得到声速与温度的表达式反推出高温下的弹性模量、泊松比,通过与理论值比较发现误差分别为3.16%、4%。Ultrasonic velocity has a direct influence on defect detection and characterization of materials,therefore,it is important to study the variation law of sound speed at different temperatures.In this paper,the propagation velocity of longitudinal wave,transverse wave and surface acoustic wave excited by laser point source at different temperatures are numerically simulated by finite element method,the relation between sound velocity and temperature of longitudinal wave,transverse wave and surface acoustic wave is obtained.According to the expression,Poisson＇ s ratio and elastic modulus are derived at high temperature.The results show that the sound velocity of longitudinal wave,transverse wave and surface acoustic wave decrease linearly with the increase of the temperature,and the change rate with temperature is 0.8374 m·s^（-1）·℃^（-1）、1.203 m·s^（-1）·℃^（-1）、1.096 m·s^（-1）·℃^（-1）,respectively.According to the expression of the sound velocity and temperature,the elastic modulus and Poisson＇s ratio at high temperature are derived,and compared with the theoretical values,the errors are 3.16% and 4%,respectively.

关 键 词：高温 声速 激光超声 有限元法 

分 类 号：TN249[电子电信—物理电子学]