Mechanical properties of bcc Fe-Cr alloys by first-principles simulations

Abstract

The effect of chromium content on the fundamental mechanical properties of Fe-Cr alloys has been studied by first-principles calculations. Within a random solid solution model, the lattice constants and the elastic constants of ferromagnetic bcc Fe1−xCrx (0⩽ · ⩽0.156) alloys were calculated for different compositions. With addition of Cr content, the lattice parameters of Fe-Cr alloys are larger than that of pure Fe solid, and the corresponding Young’s modulus and shear modulus rise nonmonotonically with the increasing Cr content. All alloys (except 9.4 at% Cr) exhibit less ductile behavior compared with pure bcc Fe. For the Fe1−xCrx (0⩽ · ⩽0.156) alloys, the average magnetic moment per atom decreases linearly with the increasing Cr concentration.