FERRITIC STAINLESS HOT-ROLLED STEEL PLATE EXCELLENT IN FORMABILITY AND METHOD FOR PRODUCTION THEREOF

• Main Authors: CHU NAYEON, KONG JUNGHYUN, KIM JINSUK
• Format: Patent
• Language: English; Korean
• Published: 03.05.2023
• 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

The present invention relates to a ferritic stainless hot-rolled steel plate with excellent formability, which has the R-bar value of 1.08 or higher after hot-rolling a steel, which comprises: 0.001-0.1 wt% of C; 10.0-14.0 wt% of Cr; 0.001-0.5 wt% of Ti; 0.001-0.5 wt% of Nb; 0.001-1.5 wt% of Ni; 0.001-1.5 wt% of Mn; 0.001-1.0 wt% of Cu; 0.001-2.0 wt% of Si; 0.001-0.1 wt% of N; 0.1 wt% or lower of Al; and residual Fe and unavoidable impurities, and after pre-rolling with a rolling rate of 30% or higher, and satisfies TS/YS <= 1.5, which shows the ratio of yield strength (YS) and tensile strength (TS). In addition, the present invention relates to a method for the production of the ferritic stainless hot-rolled steel plate with excellent formability, which comprises: a step of continuously casting the steel, which comprises: 0.001-0.1 wt% of C; 10.0-14.0 wt% of Cr; 0.001-0.5 wt% of Ti; 0.001-0.5 wt% of Nb; 0.001-1.5 wt% of Ni; 0.001-1.5 wt% of Mn; 0.001-1.0 wt% of Cu; 0.001-2.0 wt% of Si; 0.001-0.1 wt% of N; 0.1 wt% or lower of Al; and residual Fe and unavoidable impurities, and manufacturing a slab; a step of reheating the manufactured slab; a step of hot-rolling the reheated slab; a step or pre-rolling with a rolling ratio of 30% or higher; and a step of hot-rolling and annealing the slab. 본 발명은, 중량%로, C: 0.001~0.1%, Cr: 10.0~14.0%, Ti: 0.001~0.5%, Nb: 0.001~0.5%, Ni: 0.001~1.5%, Mn: 0.001~1.5%, Cu: 0.001~1.0%, Si 0.001~2.0%, N: 0.001~0.1%, Al: 0.1% 이하, 나머지 Fe 및 불가피한 불순물을 포함하는 강을 열간압연한 뒤, 30% 이상의 압하율로 pre-rolling한 후의 R-bar 값이 1.08 이상이며, 항복 강도(YS) 및 인장 강도(TS)의 비를 나타내는 TS/YS≤1.5를 만족하는 성형성이 우수한 페라이트계 스테인리스 열연강판에 관한 것이다. 또한, 본 발명은, 중량%로, C: 0.001~0.1%, Cr: 10.0~14.0%, Ti: 0.001~0.5%, Nb: 0.001~0.5%, Ni: 0.001~1.5%, Mn: 0.001~1.5%, Cu: 0.001~1.0%, Si 0.001~2.0%, N: 0.001~0.1%, Al: 0.1% 이하, 나머지 Fe 및 불가피한 불순물을 포함하는 강을 연속주조하여 슬래브를 제조하는 단계; 상기 제조된 슬래브를 재가열하는 단계; 상기 재가열된 슬래브를 열간압연하는 단계; 30% 이상의 압하율로 pre-rolling하는 단계; 및 열연 소둔하는 단계를 포함하는 성형성이 우수한 페라이트계 스테인리스 열연강판의 제조방법에 관한 것이다.