摘要
304奥氏体不锈钢由于其本身组织特性，在制造和在役过程中会产生部分铁素体和马氏体并析出，使其具有一定的磁性，即相对磁导率肼大于1，试验测试结果表明：当不锈钢件形变量在20％以内，随着形变量的增加，试件的磁导率增加，并逐渐开始具有铁磁材料的磁特性，导致不锈钢涡流检测集肤深度降低，也改变了检测的最佳激励频率。此外，通过比较2种不同激励频率的选取方法可得，在不锈钢形变量20％以内，不锈钢形变量增大，其最佳检测频率倾向于降低，且小于100kHz。试验和仿真结果表明，304不锈钢压力容器最佳检测频率范围为40—100kHz。
Due to its own microstructure characteristics, 304 austenitic stainless steels will produce some ferrite and marten site transformation which has a certain magnetic and the permeability is greater than 1in the process of manufacturing and in-service. Experimental results show that when the deformation of 304 stainless steel specimens is less than 20%, the permeability of specimens increased and gradually began to have magnetic properties of ferromagnetic materials with the deformation rate of stainless steel specimens increasing, which lead to the reducing of the skin depth of eddy current testing （ECT） and also changed the optimal excitation frequency. In addition, it can be drawn that the optimal excitation frequency will tend to reduce, and less than 100 kHz with stainless steels deformation increasing by comparing two different selection methods of excitation frequency. Experimental and simulation results show that the optimal detection frequency of ECT range is 40 - 100 kHz on 304 stainless steel pressure vessel.
出处
《失效分析与预防》
2013年第5期269-273,共5页
Failure Analysis and Prevention
基金
国家质检公益项目(201110030)
关键词
304奥氏体不锈钢
磁导率
形变
涡流检测
频率
304 anstenitic stainless steels
permeability
displacement
eddy current testing （ECT）
frequency
