Effect of similar element substitution on Fe-B-Si-Mo bulk metallic glasses studied by experiment and ab initio molecular dynamics simulation

Fe-72(B, Si, Mo)(28) bulk metallic glasses (BMGs) were successfully fabricated by conventional copper mold casting. The glass-forming ability of the Fe72B17Si5Mo6 BMG was enhanced by partial similar element substitution of Nb for Mo and Co for Fe, which was explained from the thermodynamic and atomic structural perspective. The thermal, magnetic and mechanical properties of Fe72B17Si5Mo6, Fe72B17Si5(-Mo0.5Nb0.5)(6) and (Fe0.5Co0.5)(72)B17Si5(Mo0.5Nb0.5)(6) BMGs were investigated by experiment and ab initio molecular dynamics simulation. The Fe72B17Si5Mo6 BMG shows a high saturation magnetization (M-s) of 1.08 T, a low coercivity of 3.0 A m( -1), a high compressive yield strength of 4330 MPa and an outstanding plastic strain (epsilon(p)) of 2.6%. Through similar element substitution, the M-s of (Fe0.5CO0.5)(72)B17Si5(Mo0.5Nb0.5)(6 )BMG decreases to 1.01 T owing to smaller magnetic moment of Nb and Co than Mo and Fe, and the epsilon(p) increases to 3.5% because of less 15xx pair with five-fold symmetry. (C) 2019 Elsevier B.V. All rights reserved.