Manufacturing process for aerospace bearing rolling elements
US9732394B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 17, 2012 |
| Grant date | Aug 15, 2017 |
| Priority date | — |
| Expiry date | Jun 29, 2035 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/47
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method of treating bearing rolling elements or bearing rings after a hardening and temper heat treatment is disclosed. The method may include treating the bearing rolling elements in a tumbling treatment and then in a duplex hardening treatment. The method may include treating the bearing rings in a peening treatment and then in a duplex hardening treatment. The duplex hardening treatment may also include at least one sequential process segment consisting of subjecting the bearing rolling element & rings to a nitriding process to increase the surface hardness and compressive residual stress. The combined two-step process produces a deep surface/sub-surface residual stress greater than the depth of the maximum operating von-Mises shear stress along with an ultra-hard surface with high magnitude of compressive residual stress. In so doing, the bearing ring and rolling elements will have significantly enhanced rolling contact fatigue resistance and resistance to surface imperfections and debris.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.