TI- and NB-added ferritic stainless steel excellent in low-temperature toughness of welds

A Ti- and NB-added ferritic stainless steel excellent in low-temperature toughness of welds according to an embodiment of the present invention comprises, in weight, 0.004-0.015% of C, 0.004-0.015% of N, 0.01-0.7% of Si, 0.01-0.7% of Mn, 0.0001-0.04% of P, 0.0001-0.005% of S, 10-30% of Cr, 0.005-0.04% of Al, 0.1-0.5% of Ti, 0.1-0.6% of Nb, 0.0001-0.003% of Ca, and the balance of Fe and other inevitable impurities, the ferritic stainless steel satisfying formula (1) below, wherein the Al-Ca-Ti-Mg-O-based oxide and the Ti-Nb-C-N carbonitride containing the oxide have an average diameter of 3-10 [mu]m and a distribution density of 4/mm2 or more. (1) {(Ti + 0.5*Nb)*(C + N)}/Al > 0.25. 根据本发明的一个实施方案的焊接部的低温韧性优异的添加Ti和NB的铁素体不锈钢以重量计包含：0.004％至0.015％的C、0.004％至0.015％的N、0.01％至0.7％的Si、0.01％至0.7％的Mn、0.0001％至0.04％的P、0.0001％至0.005％的S、10％至30％的Cr、0.005％至0.04％的Al、0.1％至0.5％的Ti、0.1％至0.6％的Nb、0.0001％至0.003％的Ca，以及余量的铁(Fe)和其他不可避免的杂质，铁素体不锈钢满足下式(1)，其中基于Al-Ca-Ti-Mg-O的氧化物和包含该氧化物的Ti-Nb-C-N碳氮化物具有3μm至10μm的平均直径为和4/mm2或更大的分布密度。(1){(Ti+0.5*Nb)*(