High-strength steel sheet having excellent sour resistance and manufacturing method for the same

• Main Authors: KIM YONG JIN, PARK YOEN JUNG, NOH HEE GOON, KANG SANG DEOK, JUNG YOUNG DEOK
• Format: Patent
• Language: English; Korean
• Published: 03.07.2019
• Subjects: ALLOYS; CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

According to an embodiment of the present invention, a high-strength steel sheet having excellent sour resistance comprises: 0.35-1.2 wt% of C; 16-27 wt% of Mn; 3 wt% or less (excluding 0 wt%) of V; and the remainder of Fe and inevitable impurities. The high-strength steel sheet further comprises carbides and the remaining austenite structure as a microstructure with an area ratio of 10% or less based on a cross section. Moreover, an average grain size of the carbides can be 100 nm or less, and an average grain size of the austenite structure can be 300 μm or less. 본 발명의 일 실시예에 따른 내사우어 특성이 우수한 고강도 강재는, 중량 %로, C: 0.35~1.2%, Mn: 16~27%, V: 3% 이하(0% 제외), 나머지 Fe 및 불가피한 불순물을 포함하고, 단면 기준으로 10% 이하의 면적분율로 구비되는 탄화물 및 나머지 오스테나이트 조직을 미세조직으로 포함하며, 상기 탄화물의 평균 입도는 100nm 이하이고, 상기 오스테나이트 조직의 평균 입도는 300㎛ 이하일 수 있다.