Image Number 4 for United States Patent #6666930.
The present invention offers a minute-sized magnet with superior magnetic energy product (BH).sub.max and coercivity iHc, as well as superior anti-corrosive properties. This magnet is comprised of an alloy comprised of 35-55 atomic % platinum, 0.001-10 atomic % third element, which is one or more elements from groups IVa, Va, IIIb, or IVb, and a remainder of iron and other unavoidable impurities. The average crystal size of this FePt alloy is 0.3 .mu.m. By mixing an FePt alloy with a specific element in a designated ratio, an FePt magnet with more excellent characteristics than ones made from previous alloys was successfully made.