Rolling Compaction, Magnetic Properties, and Microstructural Development During Sintering of Fe–Si

Abstract

Mixtures of atomised iron powder and FeSi17 powder have been consolidated in a rolling mill into strips containing 3%Si overall, 0·8 mm in thickness and 50 mm wide. The effect of sintering temperature and cold reduction ratio on the magnetic properties of Fe–Si strips was investigated. The relationship between the magnetic flux density and the density of the sintered strips was almost linear. Coercive force decreased with increasing sintering temperature owing to the intense sintering and the resultant grain growth. Residual induction decreased with increasing sintering temperature. Cold reduction and subsequent annealing improved the magnetic properties of the sintered strips. The microstructural development of elemental Fe–Si powder compacts and the Fe–FeSi17 powder system during sintering at between 900 and 1250°C was studied by optical microscopy. PM/0634