Isotropic tool steel
US4729872A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 1986 |
| Grant date | Mar 8, 1988 |
| Priority date | — |
| Expiry date | Sep 10, 2006 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22C38/22
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Isotropic tool steel consisting essentially of necessary elements as tool steel, less than 0.005 weight % of S and less than 30 ppm of O, the balance being substantially Fe. The necessary elements are, by weight, 0.10-0.70% of C, 2.00% or less of Si, 2.00% or less of Mn, 7.00% or less of Cr, 0.20-12.00% of W and/or Mo alone or in combination (1/2W+Mo), 3.00% or less of V. They may further include at least one of 4.00% or less of Ni, 6.50% or less of Co and 0.20% or less of N. The isotropic tool steel has cleanliness with respect to non-metallic inclusions defined by JIS G 0555 of dA60.times.400.ltoreq.0.010% and d(B+C)60.times.400.ltoreq.0.020%, and a ratio of transverse direction toughness to longitudinal direction toughness of more than 0.70. Since it is highly resistant to the generation and propagation of cracks and fracture, dies for hot working made therefrom can enjoy a long life.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.