利用全聚焦相控阵成像技术对焊缝中的未熔合和裂纹两种典型缺陷进行了检测。首先，介绍了全聚焦成像技术的基本原理；其次，设计制作了含上述缺陷的人工试块，利用CIVA软件进行裂纹和未熔合的缺陷响应研究；接着，对人工试块进行检测试验，比较了常规相控阵技术和全聚焦技术对上述两种缺陷的检测能力；最后，对试块进行常规无损检测，确定焊缝中缺陷的长度，对试块缺陷部位进行解剖，测量得到真实的缺陷埋藏深度和自身高度。检测试验及解剖结果表明：全聚焦技术对上述两种缺陷的成像具有更高的检测分辨率，对缺陷的定位和定量误差较小，可以应用于工程实践。

In this paper, the two typical defects of incomplete fusion and crack are studied by TFM (Total Focusing Method) technique. Firstly, the basic principle of TFM imaging technique is introduced theoretically. Secondly, the artificial flaw specimen containing the above defects are designed and fabricated, and the CIVA software is used to study the response of cracks and incomplete fusion. Then, the test of artificial flaw specimen is carried out, and the detection ability of conventional phased array technique and TFM technique for the above two defects is compared. Finally, conventional nondestructive testing is carried out on the specimen to determine the length of the flaws in the welds. The flaws of the specimen are dissected, and the burial depth of flaw and its own height can be measured. The results of detection and anatomy show that the TFM technique has higher detection resolution for the imaging of the above two flaws and less positioning and quantitative error, which can be applied to engineering practice.