| 摘要 |
The composite includes two or more oxides encasing the metal powder particles. The oxides form one or more common phase(s). The composite has a high magnetic susceptibility, i.e. is a soft-magnetic material. The powder comprises essentially a ferrous metal. The common phase is a glass such as a silica- or borate glass. It is alternatively a defined compound selected from: mixed oxides with spinel structure, metal phosphates and metal silicates. The mixed oxide is selected from spinel, zinc spinel, manganese spinel, iron spinel, magnoferrite, magnetite, franklinite, jakobsite, trevirite, chromite and magnochromite. Zinc- and iron phosphates are used as metal phosphates. CoSiO 3is used as a metal silicate. The starting material (also claimed) contains metal powder and separating materials with oxidic pyrolysis residues and oxidic fine powder. The separating material comprises one or more metal soaps and/or at least one of: mono-, di-, or tri-esters of phosphoric acid, of boric acid or of silicic acid with long chain alcohols and/or, if appropriate, with polydimethyl-di-siloxanes modified with reactive groups. At least one metal soap is a stearate. The metal ion in the soap is Ca, Mg, Al, Zn, Co, Fe, Ni, Cu, Mo, or Mn. The metal powder is formed from at least one metal oxide and/or silicic acid. The metal oxide is selected from Fe 2O 3, NiO, ZnO, CoO, MnO, MgO, Cr 2O 3, CuO and MoO 2. The particle diameter of the fine powder is up to about 1 mu m and no greater than 100 mu m. The proportion of separation agent, based on the weight of metal powder, is 0.1-2 wt%, or the sum of the fractions of separation agent and fine powder is 0.2-3 wt%. Further proportions are specified. |
