Precipitates in Steels With Ti Additive Produced by CSP Process

• Published in: Journal of iron and steel research, international international, 2009-07, Vol.16 (4), p.60-66
• Main Authors: LOU, Yan-zhi, LIU, De-lu, NI, Xiao-qing
• Format: Article
• Language: English
• Subjects: Applied and Technical Physics; Carbonitrides; compact strip production; CSP封装; CSP工艺; Engineering; interphase precipitation; Iron and steel industry; Machines; Manufacturing; Materials Engineering; Materials Science; Metallic Materials; Physical Chemistry; Precipitates; Precipitation; Processes; Steel making; steel with Ti additive; Steels; Strip; Titanium; titanium carbonitride; X射线衍射; 带钢生产; 沉淀物; 质量分数; 透射电子显微镜
• ISSN: 1006-706X; 2210-3988
• DOI: 10.1016/S1006-706X(09)60062-5

Hot strips of low carbon steels with Ti additive [-contain C 0.04 % -0. 07 % , Si≤0.6%, Mn≤0.6%, Ti 0. 060/00- 0.14% （mass percent）] prodvced by EAF-CSP （Electric Arc Furnaces-Compact Strip Production） process were examined by TEM, HREM and XRD. Carbonitrides with different N/C ratio were found in the sam- ples. The varying composition of the Ti-carbonitrides resulted from the supersaturation of Ti and temperature at which the compound was formed. In the tested steel, total mass fraction of the precipitates including cementite, carbonitride and a small quantity of Fe3O4, AO2O3 , Ti2 CS and A1N was about 0. 305 %. XRD results showed that about a quarter of the powder extracted by electrolysis was titanium nitrides, carbonitrides and carbides. Particle arrays formed by interphase precipitation could be observed either in slabs or in hot strips. The dominant reaction mecha- nisms were discussed. Compared with the conventional cold charge process, small amount of Ti addition would be more effective for orecipitation of fine orecioitates in the steels oroduced by CSP process.