航空铝合金薄板搅拌摩擦焊内部缺陷的超声相控阵检测

Ultrasonic Phased Array Detection of Internal Defects in the Welding Seam of Friction Stir Welded Aviation Aluminum Alloy Sheet

针对3 mm厚度下航空铝合金薄板搅拌摩擦焊焊缝的检测需求,基于典型缺陷特征以及缺陷对焊接接头性能的影响规律分析,明确了搅拌摩擦焊无损检测应重点关注的缺陷类型;设计了不同深度和尺寸的隧道以及未焊透缺陷模拟样件,利用模拟缺陷样件验证了超声相控阵检测技术对铝合金搅拌摩擦焊中1 mm埋深0.2 mm孔径的隧道缺陷以及1.6 mm埋深2 mm长、0.2 mm深未焊透缺陷的检测能力,对3 mm厚度下搅拌摩擦焊实际样件的检测结果与X射线检测结果及断口观察结果吻合,超声相控阵检测技术可以用于3 mm以下航空铝合金薄板搅拌摩擦焊焊缝的检测。

Based on the non-destructive testing requirements of welding seam in friction stir welded aviation aluminum alloy sheet with 3 mm thickness,by analyzing the typical defect characteristics of welding seam and the influence of typical defects on the properties of welded joint,the types of defects that should be paid attention to in nondestructive testing of friction stir welding zone are clarified.The samples with tunnel defects and incomplete penetration defects of different depths and sizes are designed.The samples with simulation defect are used to verify the detection ability of ultrasonic phased array detection technology on the 0.2 mm diameter tunnel defects with 1 mm depth and the 0.2 mm depth incomplete penetration defects with 1.6 mm buried depth and 2 mm length in friction stir welded aluminum alloys.The ultrasonic testing results of friction stir welded actual samples with 3 mm thickness are consistent with the X-ray test results and fracture observation results,which proves that the ultrasonic phased array testing technology can be used to detect the welding seam of friction stir welding of aviation aluminum alloy sheet below 3 mm.