Ultra-thick steel material having excellent surface part NRL-DWT properties and method for manufacturing same
US11649518B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 2017 |
| Grant date | May 16, 2023 |
| Priority date | — |
| Expiry date | Oct 7, 2038 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D2221/10
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Disclosed are a high-strength ultra-thick steel material and a method for manufacturing same. The high-strength ultra-thick steel material comprises in weight % 0.04-0.1% of C, 0.05-0.5% of Si, 0.01-0.05% of Al, 1.6-2.2% of Mn, 0.5-1.2% of Ni, 0.005-0.050% of Nb, 0.005-0.03% of Ti and 0.2-0.6% of Cu, 100 ppm or less of P and 40 ppm or less of S with a balance of Fe, and inevitable impurities, and comprises, in a subsurface area up to t/10 (t hereafter being referred to as the thickness of the steel material), bainite of 90 area % or greater (including 100 area %) as microstructures. And the particle size of crystallites having a high inclination angle boundary of 15° or higher measured by EBSD is 10 μm or less (not including 0 μm).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.