China Foundry
Title: An accelerated aging assisted by electric current in a Fe-Mn-Al-C low-density steel
Author: Zhi-gang Wang, Chu-lun Shen, Jian-lei Zhang, *Chang-jiang Song, and Qi-jie Zhai
Address: Center for Advanced Solidification Technology (CAST), School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China
Key words: low-density steel; current-assisted aging; κ-carbide
CLC Nmuber: TG142
Document Code: A
Article ID: 1672-6421(2022)05-395-08
An aging method assisted by electric current was applied to a Fe-18Mn-9Al-1C (wt.%) low-density steel. It improves the microstructure and therefore significantly increases both the yield strength and ductility of the steel. This current-assisted aging method can increase the yield strength by 178 MPa and elongation by 1.16 times in only 0.5 min at 450 °C. However, the yield strength is increased only 90 MPa by the traditional aging method (heat conduction) at 450 °C for 180 min, and the elongation is even decreased from 42.0% to 31.6%. The obvious improvement in yield strength by the current-assisted aging for a short time is resulted from the fact that the current-assisted aging promotes a rapid precipitation of nano-scale κ-carbides in γ-austenite by reducing the thermodynamic barrier and accelerating the atomic diffusion. This work demonstrates that this current-assisted aging method is significantly time saving and cost-effective for low-density steels, with potential for various industrial applications.