HIGH STRENGTH STEEL MATERIAL AND METHOD FOR MANUFACTURING SAME

摘要

The present invention relates to a steel material that enables the enhancement of tensile strength, comprising a first layer consisting of ultra low carbon steel, and a second layer that is located to be in contact with said first layer, has a first surface on the side opposite to said first layer, consists of a solid solution wherein nitrogen is dissolved in said ultra low carbon steel, and has practically the same structure as that of said first layer.