Improving mechanical properties and high-temperature oxidation of press hardened steel by adding Cr and Si

• Published in: International journal of minerals, metallurgy and materials Vol. 31; no. 8; pp. 1865 - 1875
• Main Authors: Zhu, Rong, Yang, Yonggang, Zhang, Baozhong, Zhang, Borui, Li, Lei, Wu, Yanxin, Mi, Zhenli
• Format: Journal Article
• Language: English
• Published: Beijing University of Science and Technology Beijing 01.08.2024; Springer Nature B.V; National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing,University of Science and Technology Beijing,Beijing 102206,China%Manufacturing Management Department,Ningbo Iron & Steel Co.,Ltd.,Ningbo 315800,China%Hunan Valin Lianyuan lron and Steel Co.,Ltd.,Loudi 417009,China
• Subjects: Boron steels; Carbides; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Chromium; Composites; Corrosion and Coatings; Glass; Heat resistant steels; High strength low alloy steels; High temperature; Iron oxides; Martensite; Materials Science; Mechanical properties; Metallic Materials; Microalloying; Natural Materials; Oxidation; Oxidation resistance; Research Article; Retained austenite; Scale (corrosion); Silicon dioxide; Silicon substrates; Spinel; Steel; Surfaces and Interfaces; Thickness; Thin Films; Tribology; Cr–Si micro-alloyed press hardened steel; oxidation resistance; mechanical properties; amorphous SiO; amorphous SiO2; Cr-Si micro-alloyed press hardened steel
• ISSN: 1674-4799; 1869-103X
• DOI: 10.1007/s12613-023-2796-1

This work investigated the effect of Cr and Si on the mechanical properties and oxidation resistance of press hardened steel. Results indicated that the microstructure of the Cr–Si micro-alloyed press hardened steel consisted of lath martensite, M 23 C 6 carbides, and retained austenite. The retained austenite and carbides are responsible for the increase in elongation of the micro-alloyed steel. In addition, after oxidation at 930°C for 5 min, the thickness of the oxide scales on the Cr–Si micro-alloyed press hardened steel is less than 5 µm, much thinner than 45.50 µm-thick oxide scales on 22MnB5. The oxide scales of the Cr–Si micro-alloyed steel are composed of Fe 2 O 3 , Fe 3 O 4 , mixed spinel oxide (FeCr 2 O 4 and Fe 2 SiO 4 ), and amorphous SiO 2 . Adding Cr and Si significantly reduces the thickness of the oxide scales and prevents the generation of the FeO phase. Due to the increase of spinel FeCr 2 O 4 and Fe 2 SiO 4 phase in the inner oxide scale and the amorphous SiO 2 close to the substrate, the oxidation resistance of the Cr–Si micro-alloyed press hardened steel is improved.