高频超声技术用于陶瓷零部件的无损评价和寿命预测

设计复合制作了工作频率在20～100MHz的纵波、横波以及曲面超声换能器．以延迟块直接耦合的方式对陶瓷零部件进行声参数和缺陷尺度的超声技术检测.以纵波（对气孔较灵敏）和横波（适于检测裂纹）换能器交替使用提高了可信度．在广泛检测的基础上，建立AVN（距离、波幅、当量）关系曲线，供作缺陷尺度的查判之用.基于无损的检测结果，根据断裂力学的基本原理，对陶瓷零部件作质量评价和级别判断以及取／舍裁决．

Ultrasonic Nondestructive Evaluation and Life Predication for Ceramic Parts of Engine

The longitudinal and transverse transducers having plane and curved surfaces with 20-100MHzfrequency were planed and prepared. The acoustic parameters and defect size within ceramic parts of engine were determined by means of directly coupling mode. the creditability of measurement was improved by alternately using longitudinal (susceptible to pore) and transverse (satisfying with measurement of crack) transducers. As a result of numerous measurements the relational curves of "distance- amplitude-normal" of defects were established for searching the size of defects within materials measured. On the basis of determination, according to the theory of fracture mechanics, the quality evaluation and classification of ceramic parts can be made for judgment of pass/abandonment.