采用相控阵超声检测技术,通过声学特性分析、模拟仿真、试块设计和验证试验,对304L不锈钢薄壁小径管焊缝的相控阵超声检测进行了研究。试验结果表明,对于未熔合、未焊透、裂纹等面积型缺陷,相控阵超声和射线检测的检出率均为100%。对于体积型缺陷,相控阵超声检测能力和射线检测相当;对于直径0.5 mm以下的小缺陷,受缺陷形貌、性质的影响,其反射波幅存在一定偏差。另外,相控阵超声检测的可达性和自检测效率优于射线检测的,且具有可进行交叉施工,结果数据可复查,数据重复性好,无辐射风险。

Using phased array ultrasonic testing method, this paper, through the analysis of the acoustic characteristics simulation, block design and validation test, the phased array ultrasonic testing of 304 L stainless steel thin-wall weld of small tube is under study, results of on-site verification show that for incomplete fusion area type defects such as cracks, incomplete fusion, the detection rate of phased array ultrasonic and X-ray detection is 100%.For volumetric defects, the phased array detection ability is similar to that of radiographic detection. For small defects about 0.5 mm, there is a certain deviation in reflected wave amplitude due to the influence of defect morphology and properties. In addition, the detection accessibility of PAUT is better than that of radiographic detection, and its detection efficiency is higher than that of radiographic detection. Moreover, alternating construction can be carried out, and the result data can be reviewed with good data repeatability and no radiation risk.