Patent ID: 10301701

Abstract:
Disclosed is a high-strength hot-dip galvanized steel sheet produced from a steel sheet containing Si and Mn as a base material and a method for producing the same. The method using the following conditions for a heating process for annealing: (1) The rate of temperature rise when the temperature inside an annealing furnace is in a temperature range of from 450° C. to A° C. inclusive (where A is an arbitrary value selected in a range of 500≤A) is 7° C./sec. or more; (2) The maximum steel sheet temperature reached during the annealing is 600° C. or higher and 750° C. or lower; (3) When the temperature of the steel sheet is in a temperature range of from 600° C. to 750° C. inclusive during the annealing, the transit time of the steel sheet is 30 seconds or longer and 10 minutes or shorter, and the dew point of an atmosphere is −45° C. or lower.