Study on Residual Stress and Ultrasonic Deformation Control of Titanium Alloy Cylinder Components

The distribution of residual stress in titanium alloy cylinder component is uneven, and there is stress concentration field in cylinder, which leads to serious processing deformation, bad tensile strength and poor fatigue resistance for component. The residual stress gradient testing was measured by critical refracted longitudinal wave (LCR wave) before and after ultrasonic regulation, and the residual stress in cylinder blank was reduced and homogenized by the method of high-energy acoustic beam regulation. The wall thickness of cylinder had effect on the distribution of residual stress and the stress control of the blank had positive influence on the subsequent processing effect. The results showed that the reduction rate of residual stress values in semi-finishing machining cylinders after regulation were more than 65% compared with that before regulation, and the homogenization rate of residual stress distributions after regulation were enhanced by more than 60% compared with that before regulation. The deformations of roundness were less than or equal 0.1 mm after ultrasonic regulation, which makes the cylinders satisfy the requirement of machining accuracy and have capability on stable shape preservation, explaining that the machining deformation can be effectively controlled by using the method of high-energy ultrasonic wave regulation. X-rays non-destructive method was used to macroscopically analyze the quality defects of cylinders, representing that the occurrence of structural quality defects in cylinders was inhibited effectively by using ultrasonic regulation technology.