Patent classifications
C22C38/005
Low-heavy rare earth magnet and manufacturing method thereof
The disclosure relates to a method of preparing a low-heavy rare earth magnet comprising the following steps: S1, smelting and strip casting of the raw materials of a NdFeB alloy to obtain a NdFeB alloy sheets, and mechanically crushing the NdFeB alloy sheets into flaky alloy sheets; S2, mechanically mixing the flaky alloy sheets, a low melting point powder and a lubricant to obtain a mixture, followed by hydrogen absorption and dehydrogenation treatment of the mixture and jet milling of the product to obtain a NdFeB magnet powder; S3, pressing, forming and sintering the NdFeB magnet powder to obtain a sintered NdFeB magnet; S4, mechanically processing the sintered NdFeB magnet to a desired shape, and then forming a diffusion source film on the surface of the sintered NdFeB magnet; and S5, performing a diffusion process and aging to obtain the low-heavy rare earth magnet.
HIGH STRENGTH STEEL SHEET HAVING EXCELLENT WORKABILITY AND METHOD FOR MANUFACTURING SAME
Provided is a steel sheet and a method for manufacturing the same, the steel sheet, which can be used for automobile parts and the like, having superb bendability, and excellent balance of strength and ductility and of strength and hole expansion ratio.
HIGH STRENGTH STEEL SHEET HAVING EXCELLENT WORKABILITY AND METHOD FOR MANUFACTURING SAME
Provided is a steel sheet which can be used for automobile parts and the like, and relates to a steel sheet having an excellent balance of strength and ductility, an excellent balance of strength and hole expansibility and excellent bending workability, and a method for manufacturing same.
HIGH-STRENGTH SEAMLESS STAINLESS STEEL PIPE FOR OIL WELL
To provide a high-strength seamless stainless steel pipe for oil well that has high strength, is excellent in hot workability, has excellent carbon dioxide gas corrosion resistance, and is excellent in SSC resistance under a low temperature environment. A high-strength seamless stainless steel pipe for oil well having a composition containing the particular components, the balance being Fe and unavoidable impurities, and satisfying certain expressions, having a number density of an inclusion having a major axis of 5 μm or more and 0.5<Ti/(Ti+Al+Mg+Ca)<1.0 of 0.5 per mm.sup.2 or more and 3 per mm.sup.2 or less, and having a yield strength of 655 MPa or more, wherein in 0.5<Ti/(Ti+Al+Mg+Ca)<1.0, Ti, Al, Mg, and Ca represent the contents (% by mass) of the elements in the inclusion, and an element that is not contained is designated as 0.
METHOD FOR PULVERIZING A WASTE MAGNET AND A WASTE MAGNET POWDER PRODUCED USING THE METHOD
Disclosed are a method for pulverizing a waste magnet and a waste magnet powder produced by the method. More particularly, disclosed is a method for efficiently producing a waste magnet powder having a small average particle size by pulverizing a raw material containing a hydrogen-occluded rare earth metal before dehydrogenation of the raw material.
Alloy for overlay welding and reaction tube
The present invention provides an alloy for overlay welding with which an alumina barrier layer containing an Al oxide can be formed on a projection that is overlay welded on an inner surface of a reaction tube, and a reaction tube having a projection that is overlay welded on the inner surface as a stirring member. An alloy for overlay welding according to the present invention is an alloy for overlay welding that is to be used in overlay welding, and the alloy contains C in an amount of 0.2 mass % to 0.6 mass %, Si in an amount of more than 0 mass % to 1.0 mass %, Mn in an amount of more than 0 mass % to 0.6 mass % or less, Cr in an amount of 25 mass % to 35 mass %, Ni in an amount of 35 mass % to 50 mass %, Nb in an amount of 0.5 mass % to 2.0 mass %, Al in an amount of 3.0 mass % to 6.0 mass %, Y in an amount of 0.005 mass % to 0.05 mass %, wherein Y/Al is 0.002 or more to 0.015 or less; and the balance being Fe and inevitable impurities.
Cast iron inoculant and method for production of cast iron inoculant
An inoculant for the manufacture of cast iron with spheroidal graphite is disclosed, the inoculant has a particulate ferrosilicon alloy having between 40 and 80% by weight of Si; 0.02-8% by weight of Ca; 0-5% by weight of Sr; 0-12% by weight of Ba; 0-15% by weight of rare earth metal; 0-5% by weight of Mg; 0.05-5% by weight of Al; 0-10% by weight of Mn; 0-10% by weight of Ti; 0-10 by weight of Zr; the balance being Fe and incidental impurities in the ordinary amount, wherein the inoculant additionally contains, by weight, based on the total weight of inoculant: 0.1 to 15% of particulate Sb.sub.2S.sub.3, and optionally between 0.1 and 15% of particulate Bi.sub.2O.sub.3, and/or between 0.1 and 15% of particulate Sb.sub.2O.sub.3, and/or between 0.1 and 15% of particulate Bi.sub.2S.sub.3, and/or between 0.1 and 5% of one or more of particulate Fe.sub.3O.sub.4, Fe.sub.2O.sub.3, FeO, or a mixture thereof, and/or between 0.1 and 5% of one or more of particulate FeS, FeS.sub.2, Fe.sub.3S.sub.4, or a mixture thereof, a method for producing such inoculant and use of such inoculant.
SHOCK ABSORBING MEMBER, METHOD FOR PRODUCING SHOCK ABSORBING MEMBER, AND METHOD FOR PRODUCING STEEL SHEET FOR COLD PLASTIC WORKING
A shock absorbing member which can increase impact absorption energy and also enables thinning of a steel sheet that is a starting material, a method for producing the shock absorbing member, and a method for producing a steel sheet for cold plastic working are provided. The shock absorbing member includes a ridge portion formed in a curved shape as viewed from a longitudinal direction, and a wall portion extending from the ridge portion. In the wall portion, a ratio σ.sub.5/τ.sub.5 between a tensile stress σ.sub.5 when an elongation in a tensile test is 5% and a shear stress τ.sub.5 when a shear strain in a shear test is 5√3% is 1.70 or less, or a ratio σ.sub.10/τ.sub.10 between a tensile stress σ.sub.10 when an elongation in a tensile test is 10% and a shear stress τ.sub.10 when a shear strain in a shear test is 10√3% is 1.70 or less.
HEAVY RARE EARTH ALLOY, NEODYMIUM-IRON-BORON PERMANENT MAGNET MATERIAL RAW MATERIAL, AND PREPARATION METHOD
Disclosed in the present invention are a heavy rare earth alloy, neodymium-iron-boron permanent magnet material, a raw material, and a preparation method. The heavy rare earth alloy comprises the following components: RH: 30-100 mas %, not including 100 mas %; X, 0-20 mas %, not including 0; B: 0-1.1 mas %; and Fe and/or Co: 15-69 mas %, RH comprising one or more heavy rare earth elements in Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Sc, and X being Ti and/or Zr. When the heavy rare earth alloy of the present invention is used as a sub-alloy to prepare the neodymium-iron-boron permanent magnet material, a high utilization rate of heavy rare earth is achieved, so that the coercivity can also be greatly improved while the neodymium-iron-boron permanent magnet material maintains high remanence.
STEEL FOR ALLOY STRUCTURE AND MANUFACTURING METHOD THEREFOR
Disclosed is a steel for an alloy structure, the chemical elements of the steel being, in percentage by mass: 0.35-0.45% of C, 0.27-0.35% of Si, 0.6-0.8% of Mn, 0.015-0.05% of Al, 0.06-0.1% of V, 0.2-1.0% of Zr, 0.001-0.005% of Mg, 0.025% or less of P, 0.015% or less of S, 0.005% or less of N, 0.001% or less of 0, the balance being Fe and other inevitable impurities. In addition, also disclosed is a manufacturing method for the steel for an alloy structure, the method comprising steps of: (1) smelting, refining, and casting; (2) blooming and cogging; (3) secondary hot rolling to form a product; and (4) heat treatment including quenching and tempering. The steel for an alloy structure is designed by adding trace alloy elements, the steel for an alloy structure is further strengthened and toughened, and the manufacturing cost is low.