Self-shielded flux cored wire of excellent impact toughness at post weld heat treatment

Provided is a self-shielded flux cored wire for all position welding with excellent post-heat treatment impact toughness. A flux constituting the self-shielded flux cored wire of the present invention includes, based on the total weight of the wire, 7.0-16.0 wt% of BaF_2, 0.2-1.7 wt% of CeO_2, 1.0-2.1 wt% of Al, 1.5-2.1 wt% of Mg, 0.2-1.7 wt% of LiF, 0.2-0.4 wt% of BaCO_3, 1-3 wt% of iron oxide, 0.4-0.8 wt% of Mn, 0.7-1.6 wt% of Ni, and the remaining balance consisting of iron and unavoidable impurities, and value A defined by the relational expression 1 satisfies 0.8-1.7. 후열처리 충격인성이 우수한 전자세용 셀프 실드 플럭스 코어드 와이어가 제공된다. 본 발명의 셀프 실드 플럭스 코어드 와이어를 이루는 플럭스는, 와이어 전중량에 대한 중량%로, BaF: 7.0~16.0%, CeO: 0.2~1.7%, Al: 1.0~2.1% 및 Mg: 1.5~2.1%, LiF: 0.2~1.7%, BaCO: 0.2~0.4%, 산화철: 1~3%, Mn: 0.4~0.8%, Ni: 0.7~1.6%, 잔부 철분 및 불가피한 불순물을 포함하고, 관계식 1에 의해 정의되는 값 A가 0.8~1.7을 만족한다.