Perpendicularly Crystallized Ribbons by Means of Rapid Solidifications from Melts

Abstract

ABSTRACTSilicon-iron alloy ribbons containing around 6 wt% silicon and Sendust alloy ribbons in the crystalline state were prepared by a rapidly quenching roll method. In the as-prepared ribbons columnar grains about 1Oμm in diameter wer observed to grow from the surface to the middle part of the ribbon thickness. For the high silicon-iron ribbons annealed at 1200°C for 30 minutes the grain size was more than 1 mm and the texture was highly oriented to (100)[0kl] cube-on-face. The coercive force was 55 mOe for the 6.6Si 93.4Fe ribbons annealed at 1180°C for 60 minutes in vacuum, and the average magnetic iron loss W15/50 and W10/50 of the ribbons having the coercive force of 80 mOe was 0.7 Watt/kg and 0. 25 Watt/kg, respectively. For Sendust ribbons, the lowest coercive force was 8mOe when the ribbons was annealed at 1040°C for 30 minutes and then cooled at the rate of 60 deg/hour down to 550°C in vacuum. The recording heads made of laminated Sendust ribbons exhibit much better recording characteristics than ferrite heads, while frequency response remains flat.