Structural, electronic, magnetic and mechanical properties of Fe2SiC

• Published in: Physica. B, Condensed matter Condensed matter, 2021-10, Vol.618, p.413136, Article 413136
• Main Authors: Liang, X., Hou, T.P., Zhang, D., Zheng, P., Lin, H.F., Li, Y., Wu, K.M.
• Format: Article
• Language: English
• Subjects: Anisotropy; Atomic structure; Cementite; Chemical bonds; Covalent bonds; Elastic anisotropy; Electronic properties; First principles; First-principles calculations; M3C carbides; Magnetic features; Magnetic fields; Magnetic properties; Mechanical properties; Modulus of elasticity; Phase stability; Physical properties; Shear modulus; Silicon; Studies; Substitution reactions
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2021.413136

First-principles calculations have been implemented to investigate the substitutional solute of Si in cementite. The thermodynamical stability of Fe2SiC is better than other M3C compounds according to the reaction energy. The magnetic features of Fe2SiC origin from the Wyckoff sites of Si atoms, the octahedron structure unit and the Fe–C bond distances. The bonding in Fe2SiC has a mixture of covalent, metallic and ionic characteristics and the substitution of Si increases the degree of the covalent bonds. The Young's modulus and shear modulus increase whereas the degree of elastic anisotropy decreases with the Si-substitution for the mechanical stable Fe2SiC. The investigation provides a theoretical prediction for the precipitated phases and their physical properties in silicon-containing steels. •The substitution of Si for Fe at the 4c sites can improve M3C stability.•The magnetic features of Fe2SiC origin from the Wyckoff sites of Si atoms, the octahedron structure unit and the Fe-C bond distances.•Si-substitution strengthens the degree of covalent bonds and increases the corresponding mechanical property.