Abstract: A magnetically soft powder composite material is described, which is composed of at least 99.4 wt. % of a pure iron powder, a phosphatized iron powder, or an iron alloy powder and 0.05 wt. % to 0.6 wt. % of a soft ferrite powder and which is primarily suited for use in rapidly switching solenoid valves in motor vehicle engines. Furthermore, a method for manufacturing such a magnetically soft powder composite material includes the following method steps: a) preparation of a starting mixture including a pure iron powder, a phosphatized iron powder, or an iron alloy powder and a soft ferrite powder, b) mixing of the starting mixture, c) compacting of the starting mixture in a press under increased pressure, d) debinding of the compacted starting mixture in an inert gas atmosphere or in an oxygen-containing gas atmosphere, and e) heat treatment of the compacted starting mixture in an oxidizing gas atmosphere at a temperature of 410° C. to 500° C.

Abstract: A magnetically soft powder composite material is described, which is composed of at least 99.4 wt. % of a pure iron powder, a phosphatized iron powder, or an iron alloy powder and 0.05 wt. % to 0.6 wt. % of a soft ferrite powder and which is primarily suited for use in rapidly switching solenoid valves in motor vehicle engines. Furthermore, a method for manufacturing such a magnetically soft powder composite material includes the following method steps: a) preparation of a starting mixture including a pure iron powder, a phosphatized iron powder, or an iron alloy powder and a soft ferrite powder, b) mixing of the starting mixture, c) compacting of the starting mixture in a press under increased pressure, d) debinding of the compacted starting mixture in an inert gas atmosphere or in an oxygen-containing gas atmosphere, and e) heat treatment of the compacted starting mixture in an oxidizing gas atmosphere at a temperature of 410° C. to 500° C.

Abstract: A sintered, magnetically soft composite is proposed, especially for use in solenoid valves, and a process for producing such a composite, in which initially a starting mixture from which the magnetically soft composite is formed after sintering is produced, having a ferromagnetic, especially powdery first starting component (11) as main constituent, and a ferritic second starting component (12) as secondary constituent, as well as possibly a pressing aid. After the starting mixture is sintered, the second starting component (12) is present in the produced composite at least largely as grain boundary phase. The proposed manufacturing process includes the process steps: provision of the starting mixture; mixing of the starting mixture; compression of the starting mixture in a cavity mold under increased pressure; removal of the binder from the compressed starting mixture; and sintering of the compressed starting mixture to form the composite.

Abstract: A method for producing shaped bodies from hard ferrites, includes (a) providing a powder of hard ferrite material having a fine particle size; (b) adding to the powder a plastifying and bonding agent which comprises (a) at least one of cyclododecane, cyclododecanol, and stearyl alcohol and (b) stearic acid to provide a mixture; (c) shaping the mixture into a blank; (d) heating at a temperature effective to remove the plastifying and bonding agent from the blank; and (e) subsequently heating the blank to a temperature effective to sinter the powder. The method is suitable for the production of magnets, in particular segmental magnets.

Abstract: A sinter magnet based on Fe-Nd-B with improved coercive field strength and reduced temperature dependency thereof consists of 25 to 50 wt. % Nd, 0.5 to 2 wt. % B, 0 to 5 wt. % Al, 0.5 to 3 wt. % O, remainder Fe and usual impurities and has an oxygen content which is adjusted by the addition of oxygen or of oxygen-containing compounds, especially of an Al and/or Nd oxide, before the dense sintering. It is obtainable by the melting together of the pure components with formation of a pre-alloy, pulverisation of the pre-alloy, alignment of the powder in a magnetic field and pressing to a green formed body, sintering at 1040.degree. to 1100.degree. C. and subsequent annealing at 600.degree. to 700.degree. C., whereby one adds the oxygen as Al or Nd oxide or via the grinding and/or sintering atmosphere.