MAGNETIC SHAPE-MEMORY RIBBON PRODUCED BY RAPID QUENCH METHOD

Fe-Mn-Si based alloy, one of the shape memory material has slight magn etization in addition to shape memory effect (SME). We tried to improv e the magnetization on the ribbon specimen produced by rapid quench me thod. Though the magnetization curve shows only slight magnetization a s cast, it has clear SME and this worked at lower shape recovery tempe rature than the sheet type specimen. By contrast, after annealing in a ir at 600 degrees C the magnetization increases markedly while the rib bon becomes hard and fragile. We recognized that the oxidation on the surface brought by annealing caused the increase of magnetization. In order to be compatible both of the magnetization and SME we prepared 0 .5 mm thick sheet. Oxidation by annealing was applied only on the surf ace and then the specimen was found to have both properties.