Method and apparatus for producing beneficial stresses around apertures by use of focused stress waves, and improved fatigue life products made by the method
US6230537A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 22, 1999 |
| Grant date | May 15, 2001 |
| Priority date | — |
| Expiry date | Sep 22, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T403/75
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
Metal coldworking tooling and a method of employing such tooling. The tooling is used to produce deformation in a workpiece, preferably via use of stress waves, to provide a selected beneficial residual stress profile in the workpiece, in order to provide high fatigue life structures in a minimum number of manufacturing steps. Preferably, action of an indenter causes propagation of stress waves to coldwork a workpiece, causing dimples in the workpiece. Preferably, the dimples are provided with a shape formed by application of a uniform pressure profile to the workpiece surface. By optimized use of the method, a relatively uniform beneficial residual stress profile is provided at both the surface and at the midplane apertures in a workpiece, so as to improve overall fatigue life. An improved indenter tool profile shape is described, having a smoothly curved indenter surface portion. Also, the use of a consumable lamina wafer technique provides the benefit of easy application of uniform stress profile to a workpiece.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.