An aluminum alloy material has a composition containing 3% by mass or more and 10% by mass or less of Fe and the balance of Al and incidental impurities, and a structure including a matrix and a compound. The matrix is composed mainly of Al, the compound contains Al and Fe, and a relative density is 85% or more. In any cross section, the matrix has an average crystal grain size of 1,100 nm or less, and the compound has an average major-axis length of 100 nm or less.

Boron-based amorphous alloys and a preparation method thereof is provided. The composition formula of the alloys is B.sub.aCo.sub.bRE.sub.cX1.sub.dX2.sub.eX3.sub.f, wherein RE is any one or more of La, Ce, Pr, Nd, Sm, Gd, Dy, Er and Y; X1 is any one or more of C, Si and Al; X2 is any one or two of Fe and Ni; X3 is any one or more of Zr, Nb, Mo, Hf, Ta and W; and a, b, c, d, e and f respectively represent atomic percent of each corresponding element in the formula, where: 45≤a≤55, 25≤b≤40, 10≤c≤20, 0≤d≤10, 45≤a+d≤55, 0≤e≤20, 25≤b+e≤40, 0≤f≤3, 10≤c+f≤20 and a+b+c+d+e+f=100. The preparation method of the boron-based amorphous alloy comprises: preparing master alloy ingots using an arc furnace or an induction melting furnace; and then obtaining amorphous ribbons with different thicknesses by a single copper roller melt-spinning equipment.

An aluminum (Al) alloy consisting of titanium (Ti) with a proportion of 0.1 wt % to 15 wt %; scandium (Sc) with a proportion of 0.1 wt % to 3.0 wt %; zirconium (Zr) with a proportion of 0.1 wt % to 3.0 wt %; manganese (Mn) with a proportion of 0.1 wt % to 3.0 wt %; and a balance Al and unavoidable impurities with a total of less than 0.5 wt %. The alloy is used in an additive manufacturing method for manufacturing high strength, high ductile lightweight parts for aircraft. The alloy may be initially produced as a powder that is remelted during the manufacturing process.

A soft magnetic powder has a composition represented by Fe.sub.xCu.sub.a(Nb.sub.1-zZn.sub.z).sub.b(Si.sub.1-yB.sub.y).sub.100-x-a-b [provided that a, b, and x are each a number whose unit is at %, and are numbers satisfying 0.3a2.0, 2.0b4.0, and 73.0x79.5, and y is a number satisfying f(x)y<0.99, in which f(x)=(410.sup.34)x.sup.17.56, and z is a number satisfying 0<z1.0], and contains a crystalline structure having a particle diameter of 1.0 nm or more and 30.0 nm or less at 30 vol % or more.

A soft magnetic powder has a composition represented by Fe.sub.xCu.sub.a(Nb.sub.1-zZn.sub.z).sub.b(Si.sub.1-yB.sub.y).sub.100-x-a-b [provided that a, b, and x are each a number whose unit is at %, and are numbers satisfying 0.3a2.0, 2.0b4.0, and 73.0x79.5, and y is a number satisfying f(x)y<0.99, in which f(x)=(410.sup.34)x.sup.17.56, and z is a number satisfying 0<z1.0], and contains a crystalline structure having a particle diameter of 1.0 nm or more and 30.0 nm or less at 30 vol % or more.

Disclosed are an MnBi sintered magnet exhibiting excellent thermal stability as well as excellent magnetic characteristics at high temperature, an MnBi anisotropic complex sintered magnet, and a method of preparing the same.

Disclosed are an MnBi sintered magnet exhibiting excellent thermal stability as well as excellent magnetic characteristics at high temperature, an MnBi anisotropic complex sintered magnet, and a method of preparing the same.

A negative electrode active material includes a silicon-based alloy represented by Si-M.sub.1-M.sub.2-CB, wherein M.sub.1 and M.sub.2 are different from each other and are each independently selected from magnesium, aluminum, titanium, vanadium, chromium, iron, cobalt, nickel, copper, zinc, gallium, germanium, manganese, yttrium, zirconium, niobium, molybdenum, silver, tin, tantalum, and tungsten. In the silicon-based alloy, Si is in a range of about 50 at % to about 90 at %, M.sub.1 is in a range of about 10 at % to about 50 atom %, and M.sub.2 is in a range of 0 at % to about 10 at %, based on a total number of Si, M.sub.1, and M.sub.2 atoms. C is in a range of about 0.01 to about 30 parts by weight, and B is in a range of 0 to about 5 parts by weight, based on a total of 100 parts by weight of Si, M.sub.1, and M.sub.2.

A method for producing a water-atomized metal powder, comprising applying water to a molten metal stream, dividing the molten metal stream into a metal powder, and cooling the metal powder, wherein the metal powder is further subjected to secondary cooling with cooling capacity having a minimum heat flux point (MHF point) higher than the surface temperature of the metal powder in addition to the cooling and the secondary cooling is performed from a temperature range where the temperature of the metal powder after the cooling is not lower than the cooling start temperature necessary for amorphization nor higher than the minimum heat flux point (MHF point).

Provided are an auxiliary alloy casting piece, a high-remanence and high-coercive force NdFeB permanent magnet, and preparation methods thereof. The method for preparing the auxiliary alloy casting piece includes the following steps: providing an auxiliary alloy material including, by mass percentage, 40% to 45% of Pr, 1% to 2% of Co, 0.5% to 1% of Ga, 0.6% to 0.8% of B, 0.1% to 0.2% of V, 0.3% to 0.7% of Ti, and a balance of Fe; smelting the auxiliary alloy material to obtain a smelted material; and subjecting the smelted material to a quick-setting casting to obtain the auxiliary alloy casting piece; where the quick-setting casting includes a refining and a casting in sequence.