Fe-Si-Al Ternary Alloys by Powder Metallurgy and Their Electro Magnetic Properties

Abstract

The author reported previously the manufacturing of Sendust alloy sheets by powder rolling or electric discharge sintering process.So far as magnetic properties are concerned, the products are slightly inferior to the Sendust alloy melted, owing to the fact that the density of these samples is lower than that of the latter, and also to the fact that their chemical compositions were not controlled correctly.In this experiment, the author examined some properties of sintered Sendust-alloys without or with the addition of phosphorous and titanium. Materials used were mother alloy-(6.4% Al, 11.71% Si, Fe balanced), electrolytic iron-, carbonyl iron-, red-phosphorous-, ferro-phosphorous-and ferro-titanium-powders.The compacts of the Sendust alloy (5.3% Al, 9.7% Si, Fe balanced) were obtained by pressing the mixture of 83% mother alloy and 17% iron-powders. In these compacts, the electrolytic iron powder was found to be a better binder than the carbonyl iron powder.Sintered Sendust-alloys showed the following excellent properties. But the effects of the addition of P and Ti were not so remarkable.Effective permeability of sintered Sendust alloy sheets (0.71mm thick) was higher than that of Alperm sheets (0.6mm thick).The Sendust sheet will be more superior to the Alperm sheet for the same thickness, since the frequency characteristic depends on the thickness. Electro-magnetic and physical properties of a typical sample are as follows : Um=20000, BHC=0.08 Oersted : Br=1900 Gauss : B10=7300 Gauss : D=6.49g/cm3 : ρ=133 μΩ-cm : Hv=496. This sample was sintered at 1150°C for 3hr in vacuum.