Patent · US Expired

Method of manufacturing high strength low alloys steel plates with superior low temperature toughness

US4184898A · kind A · utility

16Cited by
3References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 11, 1978
Grant dateJan 22, 1980
Priority date
Expiry dateJul 11, 1998

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC21D2211/005
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A steel slab or bloom containing 0.3.about.0.15% by weight of C, 0.05.about.0.60% by weight of Si, 0.60.about.2.5% by weight of Mn, 0.010.about.0.15% by weight of Nb, 0.005.about.0.10% by weight of soluble Al and the remainder of iron is heated to such a temperature region above 1050.degree. C. and below the reheating temperature where the austenitic grain size would be 150.mu.. The heated slab or bloom is then hot rolled with total rolling reduction of more than 40% with respect to a finished thickness at the non-recrystallized austenitic region and the hot rolled stocks are subjected to accelerated cooling at a rate of 5.degree..about.20.degree. C./sec. from a temperature higher than the Ar.sub.3 transformation point to a temperature within 550.degree..about.650.degree. C. Finally the stocks are air cooled.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.