| ‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘ KAWASAKI STEEL TECHNICAL REPORT No.22 ( May 1990 ) Advanced Technologies of Iron and Steel, Commemorating the 20th Anniversary of the Technical Research Division ‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘ |
| Progress of Continuous Annealing Technology for Cold-Rolled Sheet Steels and Associated Product Development Hideo Abe, Susumu Satoh |
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Synopsis : History of continuous annealing (CA) technology has been reviewed from a metallurgical viewpoint, and manufacturing principles for some new products developed by CA process are described as follows; (1) In 1936, Hague et al. proposed the CA principle characterized by the process including over-aging. Commercial CA lines for cold-rolled sheet steels were installed at Japanese steel companies in the 1970s. (2) Dual-phase high-strength steels were developed by applying the rapid cooling potential. (3) Drawing quality steels (CQ and DQ grades) with low C steels, hot-coiled at a high temperature, were produced by the CA process including rapid cooling and over-aging. (4) Ti-and/or Nb-added extra-low C steels provided CQ to EDDQ grade sheet steels with no over-aging CA process. (5) Bake-hardenable and extra-deep-drawable steels were developed by the high temperature CA process with Nb-bearing extra-low C steels. (6) From the view points of productivity and product quality, it is predicted that the CA process will globally evolve in the future. |
| TextiPDF: 9p./417kbj |