聚乙烯电熔接头表面不规则对超声相控阵检测的影响分析

超声相控阵技术及B扫描实时成像技术，可以实现对表面平整的聚乙烯电熔接头缺陷的检测。然而针对表面不规则的聚乙烯电熔接头进行检测，由于耦合剂与聚乙烯两者声速与声阻抗的差异，会造成检测盲区的增大、检测图像的畸变和灵敏度的降低。对聚乙烯电熔接头表面不规则对超声相控阵检测的影响进行系统地分析和研究，并探索出一种实用的方法可以消除表面不规则对超声相控阵检测的影响，使超声相控阵技术能够用于表面不规则的聚乙烯电熔接头的质量检测。

Analyse on the Influences of the Irregular Surface of Electro-fusion Joint When Tested by Phased Array Ultrasonic Technique

The testing of electro -fusion joint with smooth surface in polyethylene pipe can be performed by phased array ultrasonic focusing technique and B -scan real image technology. However, the difference in sound velocity and acoustic impedance between couplant and polyethylene will result in the expansion of dead zone, the deformation of detection figure and the reduction of sensitivity. The influences of the irregular surface on the testing of electro - fusion joint are analyzed and discussed systematically in this paper. A practical method which can reduce the unfavorable influence caused by irregular surface is presented which shows the testing of electro - fusion joint with irregular surface can be realized by phased array ultrasonic focusing technique and B -scan real image technology.