Abstract: A method for forming a smooth interface between a weld cap and an adjacent base metal utilizing ultrasonic impact treatment. The method improves the geometric profile of a weld while imparting a compressive residual stress layer on the weld metal and base metal thereby alleviating the tensile residual stresses imparted to the metals during welding. The contouring process does not remove material, as in grinding, but plastically deforms the surface being treated producing a densified surface, in turn providing a smooth weld cap and base metal surface finish without the loss of base or weld metal thickness.

Abstract: An ultrasonic impact treatment method for remediating metal sensitization including introducing ultrasound compression wave energy through ultrasonic mechanical impulse impacts into an area of sensitized metal in a workpiece. The ultrasound compression wave energy and impulse impacts impart compressive residual stress to the workpiece thereby decreasing tensile stresses in the sensitized metal and modifying the grain structure of the workpiece. These changes to the structure of the workpiece combine to slow the rate of enrichment of alloying elements at grain boundaries within the area of sensitized metal, cause intergranular diffusion of alloying elements in the area of sensitized metal, return a portion of alloying elements in the area of sensitized metal to solution and reduce or eliminate substantially straight intergranular paths through the workpiece.

Abstract: A method for forming a smooth interface between a weld cap and an adjacent base metal utilizing ultrasonic impact treatment. The method improves the geometric profile of a weld while imparting a compressive residual stress layer on the weld metal and base metal thereby alleviating the tensile residual stresses imparted to the metals during welding. The contouring process does not remove material, as in grinding, but plastically deforms the surface being treated producing a densified surface, in turn providing a smooth weld cap and base metal surface finish without the loss of base or weld metal thickness.