搅拌摩擦焊焊缝阵列超声全聚焦成像检测技术

Detection of Friction Stir Weld by Array Ultrasonic Testing Using Total Focusing Method

针对航天薄壁铝合金搅拌焊焊缝的高精度、高分辨率检测应用需求,开展了阵列超声全聚焦成像检测技术研究。基于斜楔块耦合下横波多次反射全聚焦优化算法搭建了阵列超声检测系统,利用该系统对厚度为6 mm搅拌摩擦焊焊缝不同位置处的Φ0.35 mm横孔进行了相控阵超声扇形扫描成像和阵列超声全聚焦成像检测对比试验。试验结果表明,两种方法均能够有效检测出焊缝中心或热力影响区的横孔,但阵列超声全聚焦成像检测技术在信噪比和纵向分辨力方面更具优势,该技术的发展为航天领域复杂构件高精度、高分率、高可靠性检测难题的解决提供了新的思路和途径。

In order to meet the application requirements of high-precision and high-resolution inspection of aerospace thin-wall aluminum alloy stir welding welds,ultrasonic array testing using total focusing method was studied.The array ultrasonic testing system was built based on the multi-reflection full focus optimization algorithm of shear wave coupled with oblique wedges.The comparative test of phased array ultrasonic testing by sector scanning and array ultrasonic testing by total focusing method for theΦ0.35 mm transverse holes at different positions of the 6mm friction stir welding seam were carried out by using the developed array ultrasonic testing system.The test results show that both methods can effectively detect the transverse holes in the weld center or heat affected zone,but array ultrasonic testing by total focusing method has more advantages in signal-to-noise ratio and longitudinal resolution.The development of this technology provides a new way to solve the problems of high precision,high score rate and high reliability detection of complex components in aerospace field.