中国特种设备检测研究院，北京100029 China Special Equipment Inspection and Research Institute，Beijing 100029，China为了研究电磁检测技术检测铁素体与奥氏体异种钢焊接接头表面开口裂纹的能力，制作了Q235R与S30408异种钢横向刻槽对比试样和纵向刻槽对比试样，开展了涡流阵列检测和交流电磁场检测试验。结果表明：涡流阵列检测技术能够检测异种钢焊接接头的横向裂纹和远离铁素体与奥氏体熔合线处的纵向裂纹，但无法检出熔合线处的纵向裂纹；交流电磁场检测技术能够检测熔合线处的纵向裂纹，但无法检测出远离铁素体材料的纵向刻槽；涡流阵列检测技术与交流电磁场检测技术的组合，可以解决铁素体与奥氏体焊接接头的表面开口裂纹的检测问题。

To study the detection of the surface-breaking cracks of the ferrite and austenite dissimilar steel welded joint by means of the electromagnetic testing techniques, the transverse and longitudinal notch reference blocks based on Q235R and S30408 dissimilar steel were manufactured, and the eddy current array and the alternating current field measurement techniques were selected to test the blocks. The results show that the eddy current array technique can effectively detect the transverse cracks and the longitudinal cracks at the ferrite and austenite dissimilar steel welded joints, but is unable to detect the longitudinal cracks at the fusion line; whereas the alternating current field measurement is capable of detecting the longitudinal crack at the ferrite and austenite fusion line, but is unable to detect the longitudinal notches at far away from the ferrite area. Therefore, the combination of the eddy current array and the alternating current field measurement techniques may be used to solve the problem on the surface open crack detection of the ferrite and austenite dissimilar steel welded joint.