Method for hot dip galvanizing high tensile steel strip with minimal bare spots
US5677005A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 1995 |
| Grant date | Oct 14, 1997 |
| Priority date | — |
| Expiry date | Feb 13, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C2/024
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
In connection with the manufacture of zinc hot dip galvanized or galvannealed steel strip using a high strength, high tensile steel strip containing Si, Mn or Cr as a starting steel strip, the invention provides a method for hot dip galvanizing a high tensile steel strip with minimal bare spots which can manufacture a bare spot-free steel strip of quality in an inexpensive manner while minimizing process complications and lowered productivity. The invention is achieved by subjecting a cold rolled steel strip containing at least one component of 0.1 to 2.0% of Si, 0.5 to 2.0% of Mn, and 0.1 to 2.0% of Cr and optionally further containing up to 0.2% of P, in % by weight, to recrystallization annealing in a continuous annealing line, cooling the steel strip, removing a steel component concentrated layer at the surface of the steel strip by polishing and/or pickling, subjecting the steel strip again to heat reduction at a temperature from 650.degree. C. to a recrystallization temperature and to hot dip galvanizing in a continuous galvanizing line, and optionally effecting overplating and/or alloying or effecting alloying followed by overplating.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.