Isothermal and high retained strain forging of Ni-base superalloys
US6059904A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 23, 1997 |
| Grant date | May 9, 2000 |
| Priority date | — |
| Expiry date | May 23, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S72/709
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method combining isothermal and high retained strain forging is described for Ni-base superalloys, particularly those which comprise a mixture of .gamma. and .gamma.' phases, and most particularly those which contain at least about 40 percent by volume of .gamma.'. The method permits the manufacture of forged articles having a fine grain size in the range of 20 .mu.m or less. The method comprises the selection of a fine-grained forging preform formed from a Ni-base superalloy, isothermal forging to develop the shape of the forged article, subsolvus forging to impart a sufficient level of retained strain to the forged article to promote subsequent recrystallization and avoid critical grain growth, and annealing to recrystallize the microstructure. The method permits the forging of relatively complex shapes and avoids the problem of critical grain growth. The method may also be used to produce location specific grain sizes and phase distributions within the forged article.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.