HIGH STRENGTH STEEL SHEET HAVING EXCELLENT CRYOGENIC TEMPERATURE TOUGHNESS AND LOW YIELD RATIO PROPERTIES, AND METHOD FOR MANUFACTURING SAME

摘要

The present invention relates to a high strength steel sheet having low yield ratio properties and excellent cryogenic temperature toughness and thus is suitable to be applied to the steel material for a gas tank used for the storage of gas or the like. To this end, the present invention may optimize not only the component composition of the steel material but also a manufacture condition, thus providing a high strength steel sheet suitable for the steel material for a gas tank.