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

An ultrasonic impact method of machining a work surface of a metallic workpiece body having a diverse shape and a diverse mass comprising ultrasonically impacting a set of ultrasonic impact elements in response to a periodically vibrating ultrasonic power source, arranging the set of impact elements to strike a work surface of the workpiece body at separate external surface locations by impacting individual impact elements in the set thereagainst in a random or a controlled asymmetric ultrasonic mode, and thereby inducing sufficient kinetic energy into the individual impact elements of the set to induce upon striking the work surface both a work surface texture and sub-surface workpiece body deformations, and further comprising moving the individual impact elements between the periodically vibrating ultrasonic source and the work surface in a freely moving axial mode.

An ultrasonic impact method of machining a work surface of a metallic workpiece body having a diverse shape and a diverse mass comprising ultrasonically impacting a set of ultrasonic impact elements in response to a periodically vibrating ultrasonic power source, arranging the set of impact elements to strike a work surface of the workpiece body at separate external surface locations by impacting individual impact elements in the set thereagainst in a random or a controlled asymmetric ultrasonic mode, and thereby inducing sufficient kinetic energy into the individual impact elements of the set to induce upon striking the work surface both a work surface texture and sub-surface workpiece body deformations, further comprising establishing a designated texture pattern upon the work surface, and further comprising a surface finishing step of preparing the work surface by impacting the individual impact elements against the work surface to produce a roughened micro-surface texture for adherence of a protective coating.

An ultrasonic impact method of machining a work surface of a metallic workpiece body having a diverse shape and a diverse mass comprising ultrasonically impacting a set of ultrasonic impact elements in response to a periodically vibrating ultrasonic power source, arranging the set of impact elements to strike a work surface of the workpiece body at separate external surface locations by impacting individual impact elements in the set thereagainst in a random or a controlled asymmetric ultrasonic mode, and thereby inducing sufficient kinetic energy into the individual impact elements of the set to induce upon striking the work surface both a work surface texture and sub-surface workpiece body deformations, further comprising establishing a designated texture pattern upon the work surface, and further comprising a surface finishing step of establishing a compressed surface layer by impacting the individual impact elements against the work surface.

An ultrasonic impact method of machining a work surface of a metallic workpiece body having a diverse shape and a diverse mass comprising ultrasonically impacting a set of ultrasonic impact elements in response to a periodically vibrating ultrasonic power source, arranging the set of impact elements to strike a work surface of the workpiece body at separate external surface locations by impacting individual impact elements in the set thereagainst in a random or a controlled asymmetric ultrasonic mode, and thereby inducing sufficient kinetic energy into the individual impact elements of the set to induce upon striking the work surface both a work surface texture and sub-surface workpiece body deformations, and wherein the workpiece body is a propeller having blade, hub and fillet surfaces of irregular shapes and further comprising machining the blade, hub, and fillet surfaces by said impacting by the set of impact elements.

An ultrasonic impact machining method of reworking a metallic surface on a metallic body adapted for compressive interfacing with a mating surface comprising applying ultrasonic impact energy to the metallic surface with freely flying ultrasonically driven impact needles having an effective amount of induced kinetic energy for conversion thereof to potential energy to compress a work surface layer thereby producing the capability of exerting a compressive force to the mating surface approaching an ultimate strength of the metallic body.

An ultrasonic impact method of machining work surfaces of metallic workpiece bodies having various shapes and mass distributions at selected surface zones adapted to compressively interface mating surfaces, thereby to establish higher compressive interfacing strength levels comprising

• scanning a selected surface zone of a metallic workpiece body with sets of freely moving impacting elements,
• imparting propulsion and kinetic energy to the impacting elements in response to abutment with a periodically oscillating ultrasonic transducer energy driving surface,
• impacting the surface zone with the impacting elements to convert the kinetic energy into potential energy in a magnitude deforming both surface and adjacent sub-surface regions of the metallic workpiece body in a surface layer of significant depth to control workpiece body shape, texture, hardness, compressive stresses, contact strength, and/or fatigue limits, and to eliminate structural defects.

A method of manufacturing a metallic propeller in a final manufacturing process comprising machining propeller surfaces in an ultrasonic impact machining process, comprising:

• machining a propeller surface by impacting the surface with a freely flying impact member delivering an effective amount of kinetic energy to covert into potential energy to deform and compress surface and sub-surface impact sites on the propeller surface.

A method of ultrasonic impact surface machining a metallic body surface for applying compression forces to a mating surface for curing surface and sub-surface defects comprising:

• converting kinetic energy into potential energy to deform and compress surface and sub-surface body structure on the metallic body surface by impacting the metallic body surface with a set of individually propelled impacting elements vibrating at ultrasonic frequency ranges and moving independently from a driving transducer in a free axial mode of movement.

A method of ultrasonic impact surface machining a metallic body surface for applying compression forces to a mating surface for curing surface and sub-surface defects comprising:

• converting kinetic energy by impacting the metallic body surface with a set of individually propelled impacting elements vibrating at ultrasonic frequency ranges into potential energy to deform and compress surface and sub-surface body structure on the metallic body surface, and further comprising establishing a random or controlled aperiodic driving mode of impact for the individually propelled impacting elements in the set of impacting elements by propelling and energizing the impacting elements from a periodically vibrating surface at ultrasonic frequencies to distribute energy delivery impacts of the impacting elements at different phases of the periodically vibrating surface.

A method of ultrasonic impact machining of a work surface of a metallic body to be subjected to compressive forces interfacing with a mating surface at ambient temperatures of the metallic body to increase the output compressive force of the work surface, comprising respectively moving a small area of freely axially moving impacting element into the work surface with an effective amount of energy to compress the work surface at impact points at a duty cycle permitting the metallic body to remain substantially at ambient temperature during the machining of the work surface.

A method of altering flow characteristics of a fluid about a body comprising:

• superpositioning a micro-relief and a macro-relief in a surface of the body by ultrasonically impacting a set of ultrasonic impact elements in response to a periodically vibrating ultrasonic power source so that said set of impact elements strike against the body at separate external surface locations in a random or controlled asymmetric ultrasonic mode, the micro-relief and the macro-relief corresponding with surface vortex flow of the fluid when the fluid flows about the body.