针对奥氏体不锈钢小径管焊接接头的检测难点，开展了专用试块设计、检测参数优化、检测能力验证、缺陷分析评定等相关技术的研究，总结形成了一套相控阵超声检测工艺和评定方法。检测工艺适用于外径为32～100 mm，壁厚为4～20 mm的奥氏体不锈钢小径管焊接接头的质量评定，通过在火力发电机组安装和检修工程中的成功应用，验证了该工艺的可靠性和准确性，并有效地降低了放射源的管理风险和检测成本。该检测工艺的开发可为奥氏体不锈钢小径管焊接接头的相控阵超声检测提供参考。

In view of the difficulties in the inspection of austenitic stainless steel small diameter pipe welding joint, a series of measures were taken, such as the development of special test block design, detection parameter optimization, detection capability verification, defect analysis and evaluation, etc. Based on this, a set of inspection process and evaluation methods of using phased array ultrasonic testing technology were summarized. This testing processes is suitable for quality evaluation of austenitic stainless steel small diameter pipe welding joint with outer diameter of 32~100 mm and wall thickness of 4~20 mm. The successful application in thermal power unit installation and maintenance engineering verifies the reliability and accuracy of the process, ensures the detection quality and effectively reduces the risk of radioactive source management and detection cost. The development of this detection technology provides a feasible technical scheme for phased array ultrasonic testing of austenitic stainless steel small diameter pipe welded joint.