摘要:
Magnetic materials comprising Fe, B, R (rare earth elements) and Co having a major phase of Fe-Co-B-R intermetallic compound(s) of tetragonal system, and sintered anisotropic permanent magnets consisting essentially of, by atomic percent, 8-30% R (at least one of rare earth elements inclusive of Y), 2-28% B, no less than 50% Co, and the balance being Fe with impurities. Those may contain additional elements M (Ti, Ni, Bi, V, Nb, Ta, Cr, Mo, W, Mn, Al, Sb, Ge, Sn, Zr, Hf) providing Fe-Co-B-R-M type materials and magnets.
摘要:
An (Fe, Co)-B-R tetragonal type magnet having a high corrosion resistance, which has a boundary phase stabilized by Co and Al against corrosion, and which consists essentially of:0.2-3.0 at % Dy and 12-17 at % of the sum of Nd and Dy;5-10 at % B;0.5-13 at % Co;0.5-4 at % Al; andthe balance being at least 65 at % Fe.0.1-1.0 at % of Ti and/or Nb may be present. Alloy powders therefor can be also stabilized.
摘要:
In a method for forming an adhesive layer on the surface of a workpiece before the formation of a coating film containing a powder on the workpiece, the present invention provides a method for forming the adhesive layer having a desired thickness. This object is achieved by the following method: An adhesive layer formation medium m1 coated with an adhesive material is made to collide with a workpiece W so that the adhesive material is transferred from the adhesive layer formation medium m1 to the workpiece W and forms an adhesive layer on the workpiece. An adhesive layer having a desired thickness can be formed on the workpiece by regulating the thickness of the adhesive material applied to the surface of the adhesive layer formation medium (i.e. the amount of the adhesive material held by a single adhesive layer formation medium). This enables the thickness of the powder coating as the final product to be controlled as desired.
摘要:
A powder compaction method in which a powder p is filled by air tapping or other suitable method into a mold 1, then while the mold 1 being filled with the powder, the powder particles are bound with each other without application of force from outside the mold to form a compact C, and then the compact C is taken out from the mold 1. This method produces a variety of shapes of the compact far greater than in conventional methods, and net shape manufacturing of products with complex shapes is made possible by this method. Because this method uses far less binder compared to MIM and PIM that are expected as methods for producing products with complicated shapes, the time needed for elimination of the binder is much shorter than in MIM and PIM.
摘要:
The present invention relates to a packing method in which a material (p) is fed into a space comprising an opening (4c) for feeding the material and a space (4d) to be packed with said material, and said space is subjected to air tapping, that is, switching of air-pressure from a low air-pressure state to a high air-pressure state alternately, thereby packing the material into the space (4d) at a high packing-density. The use of air tapping for packing a material into a space makes the packing-density of the material uniform.
摘要:
A perpendicular magnetic recording medium is fabricated based on R.sub.21-60 (Fe.sub.1-y Co.sub.y).sub.z M.sub.0-10 wherein z is balance and at least 70 at % of R is Nd and/or Pr, the balance of R being one or more of other rare earth elements, and wherein y is less than 0.5 by atomic ratio. M is at least one of various additional metal elements. The Curie temperature Tc is between 70.degree. to 250.degree. C.; the saturation magnetization Ms is about 450 emu/cc or more; the uniaxial perpendicular magnetic anisotropy constant Ku of 2.5.times.10.sup.6 erg/cc or more is attained. Kerr rotation angle is 0.3 degree or more, which provides a magneto-optic recording medium. Since light rare earth elements having the collinear alignment of magnetic moment with Fe are used as a key element, it is possible to fabricate uniform perpendicular magnetic anisotropy thin films in a mass production scale at a low cost.
摘要:
Green compacts for sintered ceramic bodies and for sintered permanent magnets are produced by first preparing outside a die press machine a mold which contains a rubber portion in at least a side portion. The mold cavity is then filled with the fine powder which is to form the compact to a density which is at least 1.2 times the natural filling density of the powder. The filled rubber mold is then placed in the die press machine and compacted in the die press machine to produce the green compact. The natural filling density is obtained by allowing the powder to fall from a powder pan into the rubber mold until the powder reaches the top of the rubber mold, where the distance from the powder pan to the bottom of the rubber mold is 3.7 times the depth of the cavity of the rubber mold.
摘要:
The invention relates to Fe Nd B type alloys for permanent magnets, the permanent magnets thus obtained and a method of producing them.They have high magnetic characteristics with good temperature resistance and good resistance to atmospheric corrosion.They comprise, in at%, 12 to 18% of rare earths, 3 to 30% of Co, 5.9 to 12% of B, 2 to 10% of V, some Al and Cu, the remainder being iron and unavoidable impurities. The V can be substituted by other refractory elements (Nb, W, Cr, Mo, Ti, Zr, Hf, Ta).The method mainly involves sintering at between 1050 and 1110.degree. C. followed by annealing at between 850 and 1050.degree. C. and/or artificial ageing at between 560.degree. C. and 850.degree. C.
摘要:
An Nd-Fe-B sintered magnet which has 0.5 %/.degree.C. or more of temperature-coefficient of coercive force (iHc) and a composition that R=11-18 at % (R is one or more rare-earth elements except for Dy, with the proviso of 80 at % .ltoreq.(Nd+Pr)/R.ltoreq.100 at %), B=6-12 at %, and balance of Fe and Co (with the proviso of Co is 25 at % or less relative to the total of Co and Fe (including 0 % of Co)) and impurities, is improved to have 15 kOe or more of coercive force (iHc) by means of further containing 2-6 at % of V and modifying the minority phase such that B in excess of a stoichiometric composition of R.sub.2 Fe.sub.14 B compound-phase essentially does not form RFe.sub.4 B.sub.4 -compound minority phase but forms a finely dispersed V-T-B compound minority phase (T is fe, and in a case of containing Co, T is Fe and Co).
摘要:
Ferromagnetic material for temperature sensitive elements or parts has a direction of easy magnetization which varies depending upon temperature. The material has the formula:Nd.sub.1-u R.sub.u (Co.sub.1-x M.sub.x).sub.zwherein R is one or more rare earth elements, M is at least one element selected from the group consisting of B, Al, Si, Ti, V, Cr, Mn, Fe, Ni, Cu, Zr, Nb, Ta, Mo, W, Hf, Pd, Sn and Pb, 0.ltoreq.u.ltoreq.0.5, 0