Effects of Cu-alloying in minute quantities on the corrosion-induced mechanical degradation behaviors of medium C-based ultrahigh-strength steel in aqueous environments

Journal of Materials Research and Technology

Jin Sung Park¹  Hwan Goo Seong²  Sung Jin Kim² 

[1]Corresponding author.

[2]Department of Advanced Materials and Metallurgical Engineering, Sunchon National University, Jungang-ro, Suncheon, Jeonnam, 540-742, Republic of Korea

关键词: Ultrahigh-strength steel;    Copper;    Hydrogen embrittlement;    Corrosion;    Slow strain rate test;   

DOI  :  

来源: DOAJ

【 摘 要 】

This study examined the applicability of Cu-alloying in minute quantities to medium C-based ultrahigh-strength automotive steel with a tensile strength of more than 2000 MPa to improve the resistance to mechanical degradation caused by aqueous corrosion. Cu-alloying of this steel favored the precipitation of fine-(Ti,Mo)C particles, leading to a smaller prior-γ grain size (PAGS) and inter-lath size, resulting in higher tensile strain. In addition, Cu-alloyed steel showed the surface inhibiting characteristics in a neutral aqueous condition based on higher corrosion resistance (i.e., larger polarization resistance and less weight loss). The smaller particle size of corrosion scale (CuxFe3-xO4), more uniform surface roughness, and smaller PAGS can be the major mechanistic reasons for suppressing the reduction in the mechanical properties of Cu-alloyed ultrahigh-strength steel in the corrosive environment.

【 授权许可】

Unknown