PSM Imaging Method for Water Immersion Ultrasonic Phased Array Inspection of Diffusion Welding of Titanium Alloy

Titanium alloy is widely used in aerospace and other industrial manufacturing fields, diffusion welding is a major way to connect titanium alloy components, the quality of the connection is very important for the safe use of the components. For the detection of typical internal defects in titanium alloy diffusion welding water immersion ultrasonic phased array detection research, firstly, according to the Gaussian superposition theorem to study the effect of different water depths on the phased array acoustic field, in order to determine the appropriate water layer thickness; secondly, to establish a finite element model of titanium alloy diffusion welding with typical defects, simulate the process of water immersion ultrasonic phased array detection and acquisition of detection data; finally, the ultrasonic phased array parallel focus scan data according to the phase Finally, the ultrasonic phased-array parallel-focused scan data were subjected to frequency-domain synthetic aperture imaging based on the phase migration principle. The research results show that the use of ultrasonic phased array focus scan data for dual-media frequency domain synthetic aperture imaging, compared with the phased array conventional B-sweep imaging, at -55dB to detect the traditional imaging methods can not detect the diameter of 0.2mm micro-hole defects, other defects contrast ratio increased by an average of 6.39dB, defect location accuracy within 1.3%, the method can be used for the water immersion of titanium alloy diffusion welding defects The method can provide theoretical guidance for water immersion phased array inspection of titanium alloy diffusion welding defects.