Effects of high-intensity ultrasonic-wave emission on the weldability of aluminum alloy 7075-T6

In this work high-intensity ultrasonic wave is conducted into aluminum alloy 7075-T6 to observe the effect of emission waves on the weldability during inert gas tungsten arc (GTA) welding. Through the heat-affected zone (HAZ) and the weld, the ultrasonic-wave emissions with different paths are examined and directly correlated to I the heating time, dwell time, cooling rate, as well as peak temperature of the thermal cycle, and to the grain growth, weld penetration, and hardness of the weldment. In addition, a methodology based on the characteristic curves of the relative amplitude ratios of the reflected longitudinal wave and vertical shear wave for improving the weldability of aluminum alloy 7075-T6 is presented. (C) 2002 Elsevier Science B.V. All rights reserved.