The Effect of Ultrasonic Treatment on the Structure and Properties of AMg6 Alloy Welds

Author:  Kasimirov, Gruzd, Prokopenko
Source:  Avtom. Svarka (7), July'80 (Russian)
Doc ID:  1980016
Year of Publication:  1980
Abstract:  
A study of structural changes and optimum conditions in ultrasonic treatment of welded alloy AMg6 is presented. The welds were peened by spherical and cylindrical shot, and by needle-shaped impactors. Residual stresses in treated specimens approached yield strength values at locations 20 mm away from the weld seam; the spherical shot treatment resulted in a significant strain of the weld surface, changing stresses from tension to compression. Repeated peening treatment on both sides of the specimen smoothed the stress--strain curves. The needle-shaped impactor can treat larger areas than spherical or cylindrical shot, but it imparts lower stresses to the weld surface. It was concluded that the ultrasonic treatment significantly reduces residual weld stresses without improving strength properties. The method has been used for treating microplasma welded turbine blades and for repair of thermocouples, bellows and Cu capillaries. Descriptors: Aluminum base alloys-- Welding; Shot peening; Residual stress-- Vibration effects; Ultrasonic vibration; Tensile properties