Method for preventing or arresting crack development and propagation
AssigneeSurface Technology Holdings, Ltd.
InventorPaul S. Prevey, III
Life of this patent
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Abstract
A method for preventing or arresting the development and propagation of cracks in the material surrounding a fastener. The method includes introducing compressive residual stresses in the material surrounding the fastener. The compressive residual stresses offset the high residual tensile and applied stresses which the material may be subjected to in operation and thereby prevent or arrest the development of cracks. Using the output of a sensor, the surface treatment apparatus is positioned relative to a fastener. A compression tool is impinged against the surface of the material adjacent to the fastener and rotated around the perimeter of the fastener thereby inducing a zone of compressive residual stress.
Claims17
A method for preventing or arresting crack development and propagation in the material surrounding a fastener, the method comprising the steps of:
- locating the position of a fastener;
- positioning an apparatus for inducing residual compressive stress relative to the fastener;
- and
- inducing compressive residual stress in at least a portion of the material adjacent to the fastener.
A method for introducing compressive residual stress in the surface of a workpiece surrounding a fastener to prevent or arrest crack development and propagation, the method comprising the steps of:
- using an apparatus having a rotational actuator and a tool holder for receiving and positioning attachments relative to the axis of rotation of the tool holder;
- and
- using a compression tool adjustably positioned on the tool holder to induce residual compressive stress in the surface of the workpiece.
A method for inducing compressive residual stress in the material surrounding a fastener to prevent or arrest crack development and propagation, the method comprising the steps of:
- using at least one compression tool to induce compressive residual stress in the material surrounding a fastener;
- using a positioning device to position the compression tool relative to the fastener;
- and
- using at least one sensor for locating the fastener, the at least one sensor operatively connected to the compression tool.
Dependencies are inferred from the claim text.