MANUFACTURE OF STEEL SHEET WITH HIGH DRAWABILITY

摘要

PURPOSE:To manufacture stably a steel sheet with high drawability by properly setting the soaking and holding temp. of a steel sheet according to the carbon content of the steel and the rate of temp. rise to the soaking and holding temp. CONSTITUTION:When a cold rolled steel sheet is continuously annealed, the soaking and holding temp. T( deg.C) of the steel sheet during the continuous annealing is set according to the carbon content C(wt%) of the steel and the rate V( deg.C/sec) of temp. rise from 400 deg.C to the soaking and holding temp. T. The temp. T is controlled so as to satisfy equation I in case of <0.015wt% carbon content C and equation II in case of >=0.015wt% carbon content C.