Bulk ferromagnetic glasses prepared by flux melting and water quenching

Several ferromagnetic bulk amorphous alloys of the type Fe-(Co, Cr, Mo, Ga, Sb)-P-B-C, containing between 62 and 71 at. % Fe, have been prepared in th e form of 4-mm-diam rods. The glass synthesis consists of mechanically allo ying the constituents, purifying the melts in B2O3 flux inside fused silica tubes, and quenching the melts at cooling rates on the order of 100 K/s. A ll these glasses have a large supercooled region T-x-T-g, ranging from 35 t o 61 K, within which the glass can be shaped under a relatively small appli ed load. It is shown that the value of T-x-T-g depends strongly on the meta lloid composition. These bulk metallic glasses have very low coercivity and low hysteresis losses. (C) 1999 American Institute of Physics. [S0003-6951 (99)00927-4].