Ab-initio study on electronic, mechanical and dynamical properties of maraging steel containing coherent B2 type (Fe, Al)Ni nanoprecipitates

Abstract

The ultrastrong maraging steel containing coherent B2 type (Fe, Al)Ni nanoprecipitates possesses outstanding strength and ductility with the potential to meet the demands in aerospace, advanced energy, etc. However, its transport properties including electrical and thermal conductivities have not been systematically studied. Based on the first-principles calculations, a model of Fe-7 at%(Fe, Al)Ni alloy containing B2 type (Fe, Al)Ni coherent nanoprecipitates was constructed, and its electronic, mechanical, and dynamical properties were calculated. The results showed that its bulk modulus is 169.6 GPa and the Poisson's ratio is 0.31, which are consistent with the experimental strength and ductility reported in Nature before. In addition, its unfolding band structure and phonon dispersion spectrum prove that the ultrastrong steel also has good electrical and thermal conductivities theoretically, which is similar to that of pure Fe metal. The experimental results of electrical resistivity and thermal conductivity verify the correctness and accuracy of the calculations.