衝撃圧縮を用いた非平衡バルク磁性体の創製

抄録

Shock compression can be used to consolidate a nonequilibrium alloy or compound powders without recrystallizing or decomposition, taking advantage of the high pressure and short duration, in addition it can be used to synthesize high-pressure phases. Mechanical alloying (MA) has also recently been used for nonequilibrium materials processing, including the preparation of metastable solid solution phases, amorphous phases, nano crystals, etc. We have been preparing nonequilibrium bulk materials consisting of such metastable phases in the transition metal systems or tungsten systems, etc. by using shock compression, and investigating the physical properties. Particularly, the metastable solid solution bulk alloys in transition metal systems showed interesting magnetic properties in relation to the Slater-Poring curve. In addition, a fully-dense Sm₂Fe₁₇N_x magnet was for the first time prepared. In this review, the topical magnetic properties of these metastable alloys (Fe-Co, Fe-Cu, Fe-W) and the Sm-Fe-N magnet are shown.