Razor blade steel having high corrosion resistance and differential residual austenite content
US5275672A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Mar 12, 1991 |
| Grant date | Jan 4, 1994 |
| Priority date | — |
| Expiry date | Mar 12, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22C38/22
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Steel which is particularly useful for making a razor blade of high corrosion resistance contains more than 0.45%, but less than 0.55%, of carbon, 0.4 to 1.0% of silicon, 0.5 to 1.0% of manganese, 12 to 14% of chromium and 1.0 to 1.6% of molybdenum all by weight, in addition to iron and inevitable impurities, and has a carbide density of 100 to 150 particles per 100 square microns as annealed. The razor blade has a Vickers hardness of at least 620 and a carbide density of 10 to 45 particles per 100 square microns, and preferably has a specific distribution of residual austenite content. The improved properties of the razor blade are achieved by an improved process of heat treatment which includes austenitizing the steel at a temperature of 1075.degree. C. to 1120.degree. C., cooling it to a temperature between -60.degree. C. and -80.degree. C. for hardening it, and tempering it at a temperature of 250.degree. C. to 400.degree. C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.