Thermodynamic and Ab Initio Design of Multicomponent Alloys Based on (Fe50Mn30Co10Cr10)-xBx (x = 0, 5, 7, 10, and 15 at.%)

Rodrigo Vargas-Osorio; Laura Gabriela Torres-Mejia; Lais Mujica-Roncery; Jose Y Aguilar-Hurtado; Katherine Paredes-Gil

doi:10.3390/ma16165579

Thermodynamic and Ab Initio Design of Multicomponent Alloys Based on (Fe₅₀Mn₃₀Co₁₀Cr₁₀)-xBx (x = 0, 5, 7, 10, and 15 at.%)

Materials (Basel). 2023 Aug 11;16(16):5579. doi: 10.3390/ma16165579.

Authors

Rodrigo Vargas-Osorio¹, Laura Gabriela Torres-Mejia², Lais Mujica-Roncery², Jose Y Aguilar-Hurtado³, Katherine Paredes-Gil^{1

4}

Affiliations

¹ Departamento de Química, Facultad de Ciencias Naturales, Matemática y del Medio Ambiente, Universidad Tecnológica Metropolitana, Santiago 7800003, Chile.
² Grupo de Investigación en Materiales Siderúrgicos e INCITEMA, Universidad Pedagógica y Tecnológica de Colombia, Tunja 150003, Boyacaá, Colombia.
³ Departamento de Ingeniería Mecánica, Facultad de Ingeniería, Universidad Tecnológica Metropolitana, Santiago 7800003, Chile.
⁴ Programa Institucional de Fomento a la Investigación, Desarrollo e Innovación, Universidad Tecnológica Metropolitana, Ignacio Valdivieso 2409, Santiago 8940577, Chile.

Abstract

Multicomponent alloys have attained general interest in recent years due to their remarkable performance. Non-equiatomic alloys with boron addition as an interstitial element are being studied, exhibiting outstanding mechanical properties. In order to estimate the mechanical behavior of potential alloys, thermodynamic and ab initio calculations were utilized in this work to investigate phase stability and stacking fault energy (SFE) for (Fe₅₀Mn₃₀Co₁₀Cr₁₀)-xBx (x = 0, 5, 7, 10, and 15 at.%) systems. Thermodynamic experiments revealed two structural variations of borides, M₂B(C16) with a tetragonal structure and M₂B(CB) with an orthorhombic structure. Borides precipitate when boron content increases, and the FCC matrix becomes deficient in Mn and Cr. According to ab initio calculations, the presence of boron in the FCC and HCP structures primarily disrupts the surroundings of the Fe and Mn atoms, resulting in an increased distortion of the crystal lattice. This is related to the antiferromagnetic condition of the alloys. Furthermore, for alloys with a low boron concentration, the stacking fault energy was found to be near 20 mJ/m² and greater than 50 mJ/m² when 10 and 15 at.% boron was added. As boron concentrations increase, M₂B borides are formed, generating changes in the matrix composition prone to fault-induced phase transitions that could modify and potentially impair mechanical properties.

Keywords: CALPHAD; SQS + DFT; multicomponent alloys; stacking fault energy.

Grants and funding

This research was funded by ANID through FONDECYT projects 11200264 and 3210052. L.G.-Torres acknowledges the resources provided by UPTC under the convocation 19 of 2021, project SGI 3282. K. Paredes-Gil acknowledges the computational resources provided by the CYTED cofunded Thematic Network RICAP (517RT0529), the high-performance computing system of PIDi-UTEM (SCC-PIDi-UTEM FONDEQUIP-EQM180180), and the supercomputing infrastructure of the NLHPC (ECM-02).