Abstract:The surface damage during the use of parts will affect the interface bonding quality during remanufacturing and repair, so that reducing the bearing capacity. In order to obtain the effect of surface damage on the load carrying capacity of repaired parts, plasma arc welding was used to repair the matrix materials with different width of the surface prefabricated damage, and ultrasonic phased array was used to detect the repaired parts with three-point bending load. According to the test results, the sound path of the second bottom wave is extracted from the A-scan waveform, and the change curve of the sound path of the second bottom wave under different loads is obtained, which can get the load at the interface crack initiation of the repair part ( FA ) from the turning point of the curve. By quantifying the defects in the C-scan top view and calculating the area proportion, the change curve of the defect area proportion under different loads is obtained, which can get the load at the interface initial defect evolution of the repair part (FC ) from the turning point of the curve. The results show that both FA and FC can reflect the linear relationship between the load carrying capacity of the repaired parts and the surface damage of the matrix; on the premise of the error less than 5%, the load carrying capacity of the repaired parts decreases by 0. 1 kN for every 1 mm increase in the width of the surface damage. Moreover, compared with FA , the size of FC decreases by 11. 12%, which provides a timely and effective way to evaluate the remanufacturing quality of surface damaged parts.