由于安装制造工艺的原因，核电站辅助系统奥氏体不锈钢对接焊缝极易产生焊接热裂纹，此类热裂纹具有长度短、高度小、多集中于焊缝表面和近表面区域等特征，同时又由于奥氏体材料自身的影响，依据标准采用的体积性检测方法不能获得较好的检测效果。笔者针对特定对象，介绍了核辅助系统奥氏体不锈钢对接焊缝焊接热裂纹超声波检测技术及验证结果，为此类焊接热裂纹检测技术提供了参考。

Because of welding technology, hot cracks are easily found in the austenitic stainless steel pipe weld, and these hot cracks characters are that they always have the short length, little through wall size and most of them always appear in the surface and near surface areas of the weld. Also, because of the reason of the austenitic stainless steel material, volume inspection techniques in accordance to code can not get a good result. This paper introduces the investigative ultrasonic techniques of hot cracks for austenitic stainless steel pipe weld, including the verification of the techniques and giving some reference to the inspection techniques of such hot cracks.