焊接裂纹应力与磁记忆信号关系的实验研究

焊接裂纹产生的应力集中区是焊接构件在服役过程中最为危险的一个薄弱环节，对这个环节进行有效的安全评估，具有重要意义。金属磁记忆技术是近年来发展的一种全新的无损检测方法，它可以在地磁环境下检测铁磁构件的应力集中，从而诊断出产生（或可能产生）裂纹的危险区域。利用磁场中的高斯方程，对管线钢焊接裂纹的应力和金属磁记忆信号之间的关系模型进行了初步探讨，然后利用预制的焊接裂纹对此关系模型进行了研究预测，分析结果表明：此关系模型可满足应力检测的精度要求。

Investigation on relationship between welding cracks stress and magnetic memory signal

Stress eoncentration znnes caused hy wehting cracks are the mnst dangerous weak-links in service processes of welding works,so an effective safely evaluation of the links is of great impnrtance,As a newly developed nondestructive testing method,metal magnetic memory technology can be ttsed to detect stress concentration areas of ferromagnetic works and to diagnose dangerous regions where .racks may appear in geomagnetic envirnnments,This paper constntcted a relation model between stress of pipeline steel welding cracks and metal magnetic memory signals using the Gauss equation.and discussed the model utilizing preiabricated welding cracks. Resuhs indicated that the relation model eould meet the required precision of stress measuring.