METHOD FOR DECARBON-ANNEALING COLD ROLLED STEEL FOR USE OF SHADOW MASK

摘要

PURPOSE: A method for decarbon-annealing a cold rolled steel sheet for use of a shadow mask is provided to effectively operate a decarbonizing annealing by adjusting hydrogen density, a dew point temperature, and an annealing temperature. CONSTITUTION: A cold rolled steel sheet contains carbon for 0.001-0.003wt% of entire weight. The cold rolled steel sheet is low temperature annealed at a temperature of under 750°C while adjusting a dew point temperature for -20°C in a nitrogen and hydrogen atmosphere. Then, the steel sheet is high temperature annealed at the temperature of 750-800°C while adjusting the dew point temperature for 30-50°C in the nitrogen and hydrogen atmosphere. Herein, the hydrogen density is 3-10% for the low temperature annealing and 15-20% for the high temperature annealing.