17-4PH不锈钢磁粉检测中出现的问题分析

根据需方提出的标准要求,对某系列17-4PH不锈钢材质的军用产品进行磁粉检验时,检测出很多超标缺陷。通过分析发现,这些线性显示是由于成分和组织偏析所致,此类伪缺陷可以通过热处理方式来消除,也可以通过在生产中改变浇注系统或改善散热条件的方式来避免。联系17-4PH不锈钢工件中出现的线性显示,笔者对影响磁粉检测可靠性的因素进行了探讨,以期对同种材料磁粉检测中出现的类似缺陷提供参考。

Analysis on Magnetic Particle Testing of 17-4PH Stainless Steels

According to the agreement standard and specification,discontinuities were discovered in 17-4PH stainless steel parts for military use with the help of magnetic particle testing.It is found that these liner indications,which are common in the same materials and have seriously effects on the judgments of the final magnetic particle testing results,were induced by chemical composition and microstructure segregation.The defect indications could either be reduced by heat treatment,or be avoided by improving gating system or radiation condition.Based on the results of liner indication on 17-4PH stainless steel castings,the reliability factors which affect magnetic particle testing have been discussed.It is hoped that the present test and analysis conclusion could be for reference for similar indications in magnetic particle testing of same material.