POSCO Holdings Inc.
IRON-ALUMINUM-BASED PLATED STEEL SHEET FOR HOT PRESS FORMING, HAVING EXCELLENT HYDROGEN DELAYED FRACTURE PROPERTIES AND SPOT WELDING PROPERTIES, AND MANUFACTURING METHOD THEREFOR

Abstract:

The present invention provides an iron-aluminum-based plated steel sheet, and a manufacturing method therefor, the iron-aluminum-based plated steel sheet comprising a base steel sheet and a plated layer formed on the surface of the base steel sheet, wherein the alloy plated layer comprises: a diffusion layer comprising an Fe--Al-based intermetallic compound having a cubic structure; and an alloyed layer formed on the diffusion layer and composed of an alloy phase differing from that of the cubic structure, the thickness of the diffusion layer is 3-20 .mu.m, and the thickness of the diffusion layer is greater than 50% of the total thickness of the plated layer.