Ultrasonic impact machining of body surfaces to correct defects and strengthen work surfaces

A metallic workpiece comprising a work surface for compressively interfacing with a mating sub-surface exhibiting a work surface profile obtained by machining with ultrasound impacts of the work surface and resultant transfer of ultrasound oscillations and ultrasound stress waves at sought-for impact to the work surface and said mating sub-surface, said work surface exhibiting a pattern of small area indents compressing the workpiece and said mating sub-surface being plastically deformed to eliminate inter-granular irregularities while maintaining compressive forces therein.

A metallic body comprising:

• a working surface and a mating sub-surface region, said working surface having a plurality of indentations therein provided by ultrasound impacts in machining with a set of ultrasonic impact elements against the working surface in a random and asymmetric mode to transfer ultrasound oscillations and ultrasound stress waves at sought-for impact at the indentations to said working surface and said mating sub-surface region to provide plasticized and compressed work surface and sub-surface, the indentations arranged to correspond to values of a spacing of a surface vortex flow which forms at the working surface by a fluid as the fluid flows about the body, wherein the working surface of the metallic body, when the metallic body is in an operative mode, is immersed in said fluid in such a manner that said fluid flows across the working surface so that said fluid fills the indentations and is essentially retained therein to provide a laminar flow across the working surface.

Metallic body comprising a working surface to be subjected to compressive forces interfacing with a mating sub-surface region, each of said working surface and said mating sub-surface region having been plastically deformed and modified to a depth greater than a wear depth of the metallic body by ultrasound impacts in machining to produce the working surface with a substantially uniform pattern of small area impact points of compressed body metal resulting from high-velocity impact members striking the metallic surface, and the elimination of inter-granular irregularities, providing a compressed surface layer of increased strength permitting the compressive forces to achieve a maximum strength of the metallic body metal surface.