High formability steel sheet for the manufacture of lightweight structural parts and manufacturing process
US11427898B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 20, 2018 |
| Grant date | Aug 30, 2022 |
| Priority date | — |
| Expiry date | Sep 9, 2038 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D2211/005
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A steel sheet has a composition comprising, by weight: 0.010%≤C≤0.080%, 0.06%≤Mn≤3%, Si≤1.5%, 0.005%≤Al≤1.5%, S≤0.030%, P≤0.040%, Ti and B such that: 3.2%≤Ti≤7.5% and (0.45×Ti)−1.35≤B≤(0.45×Ti)−0.43, optionally Ni≤1%, Mo≤1%, Cr≤3%, Nb≤0.1%, V≤0.1%, the remainder being iron and unavoidable impurities resulting from the smelting. The steel sheet has a structure consisting of ferrite, at most 10% of austenite, and precipitates comprising eutectic precipitates of TiB2, the volume fraction of TiB2 precipitates with respect to the whole structure being of at least 9%, the proportion of TiB2 precipitates having a surface area lower than 8 μm2 being of at least 96%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.