PRODUCTION OF HIGH-CARBON AND HIGH-SI STEEL EXCELLENT IN COLD WORKABILITY

摘要

PURPOSE:To shorten annealing time and to improve cold workability, such as drawability, by subjecting a steel in which respective contents of C and Si are specified to hot rolling and finish rolling under respectively prescribed conditions and then applying annealing to the above steel in a short time. CONSTITUTION:A steel having a composition containing, by weight, 0.5-0.7% and C 1-3% Si is refined. This steel is hot-rolled at 900-1300 deg.C and finish- annealed at a temp. between the Ar3 transformation point and 900 deg.C and at =50% total percentage of reduction of area, by which the structure of this steel is formed into a dual-phase structure consisting of pro-eutectoid ferrite and pearlite. Then, annealing is carried out at a temp. between (Ac1-50 deg.C) and Ac1 for 20-90min.