High-strength PC steel wire
US10752974B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Jul 20, 2016 |
| Grant date | Aug 25, 2020 |
| Priority date | — |
| Expiry date | Apr 18, 2037 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D2211/009
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
This invention provides a high-strength PC steel wire having a chemical composition containing, in mass %, C: 0.90 to 1.10%, Si: 0.80 to 1.50%, Mn: 0.30 to 0.70%, P: 0.030% or less, S: 0.030% or less, Al: 0.010 to 0.070%, N: 0.0010 to 0.010%, Cr: 0 to 0.50%, V: 0 to 0.10%, B: 0 to 0.005%, Ni: 0 to 1.0%, Cu: 0 to 0.50%, and the balance: Fe and impurities. A ratio between the Vickers hardness (HvS) at a location (surface layer) that is 0.1D [D: diameter of steel wire] from the surface of the steel wire and the Vickers hardness (HvI) of a region on the inner side relative to the surface layer satisfies the formula [1.10<HvS/HvI≤1.15]. The steel micro-structure in the region from the surface of the steel wire to 0.01D (outermost layer region) consists of, in area %, a pearlite structure: less than 80%, and the balance: a ferrite structure and/or a bainitic structure. The steel micro-structure in the region on the inner side relative to the outermost layer region contains, in area %, a pearlite structure: 95% or more. The tensile strength of the steel wire is 2000 to 2400 MPa. The method of producing this high-strength PC steel wire is simple, and the high-strength PC steel wire is exce…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.