超声反射CT成象在无损检测中的应用  

APPLICATION OF ULTRASONIC REFLECTION MODE TOMOGRAPHY TO NONDESTRUCTIVE EVALUATION

作　　者：兰从庆[1] 许克克[1] 李珑[1] 童世玮[1] 熊伟[1] 

机构地区：[1]中国科学院武汉物理所

出　　处：《无损检测》1994年第10期271-274,共4页Nondestructive Testing

基　　金：中科院"八五"重点项目资助课题

摘　　要：理论分析和实验表明,超声反射CT成象中,远场处可采用X射线CT成象中的FBP方法,如果远场条件不满足,成象质量将下降。本文在FBP方法的基础上,采用沿圆弧后投影的方法,可得到较好的重建象。实验结果表明,该方法效果好、简单实用,检测系统造价低,具有很好的成象功能,在材料定量无损检测中有重要的应用价值。Filtered-backprojection method of X-ray tomography is usually utilized to obtain reconstructed images under far field condition. However,the reconstructed images will be distorted when transducer is near the object because of the wavefront curvature of ultrasound. In this case,an algorithm of filtered-backprojection a-long circular arcs is used and image distortion is eliminated. Experimental results show that a cross-sectional function of acoustical reflectivity of an object can be reconstructed very well.

关 键 词：无损检验 超声检验 工程材料 CT成象 

分 类 号：TB302.5[一般工业技术—材料科学与工程]