In an example of a method for three-dimensional (3D) printing, build material layers are patterned to form an intermediate structure. During patterning, a binding agent is selectively applied to define a patterned intermediate part. Also during patterning, i) the binding agent and a separate agent including a gas precursor are, or ii) a combined agent including a binder and the gas precursor is, selectively applied to define a build material support structure adjacent to at least a portion of the patterned intermediate part. The intermediate structure is heated to a temperature that activates the gas precursor to create gas pockets in the build material support structure.

The present invention relates to a powder mixture for iron-based powder metallurgy which is obtained by mixing an iron-based powder and at least one kind of powders selected from the group consisting of a Ca—Al—Si-based composite oxide powder and a Ca—Mg—Si-based composite oxide powder, in which with a peak height of a main phase exhibiting the highest peak intensity by X-ray diffraction as 100, the composite oxide powder has a relative height of 40% or less, with respect to the main phase, of a peak height of a second phase having the second highest peak intensity.

The present invention relates to a powder mixture for iron-based powder metallurgy which is obtained by mixing an iron-based powder and at least one kind of powders selected from the group consisting of a Ca—Al—Si-based composite oxide powder and a Ca—Mg—Si-based composite oxide powder, in which with a peak height of a main phase exhibiting the highest peak intensity by X-ray diffraction as 100, the composite oxide powder has a relative height of 40% or less, with respect to the main phase, of a peak height of a second phase having the second highest peak intensity.

The present invention relates to a method for the production of palladium(0) powder in which a palladium(0) starting powder is subjected to a thermal treatment in a furnace at a temperature of no more than 370° C. in a hydrogen gas atmosphere.

The present invention relates to a method for the production of palladium(0) powder in which a palladium(0) starting powder is subjected to a thermal treatment in a furnace at a temperature of no more than 370° C. in a hydrogen gas atmosphere.

A porous copper sintered material (10) includes: a plurality of copper fibers (11) sintered each other, wherein the copper fibers (11) are made of copper or copper alloy, a diameter R of the copper fibers (11) is in a range of 0.02 mm or more and 1.0 mm or less, and a ratio L/R of a length L of the copper fibers to the diameter R is in a range of 4 or more and 2500 or less (11), redox layers (12) formed by redox treatment are provided on surfaces of copper fibers (11, 11), and concavities and convexities are formed by the redox layer (12), and each of redox layers (12, 12) formed on each of the copper fibers (11) is integrally bonded in a junction of the copper fibers (11).

This invention relates to a preparation method of rare earth oxide dispersion strengthened fee grain tungsten materials, the mass percent of the rare earth oxide is of 0.1-2%, and the rest ingredient is W. Weigh soluble rare earth salt and tungstate, dissolve into water to made into 50-100 g/L of rare earth salt solution and 150-300 g/L of tungstate solution, respectively. Firstly, add trace alkali in rare earth salt solution to control pH in 7-8, then add organic dispersant and stir to form evenly suspended R(OH).sub.3 particle colloid (R refers to rare earth element). Secondly pour the tungstate solution into the R(OH).sub.3colloid, add trace acid to control pH in 6-7, then add organic dispersant and stir to form tungstic acid micro particles, which wrap around the colloidal particles, forming coprecipitation coating particle colloid. Thirdly, the coprecipitation coating particle colloidal is spray-dried, forming tungsten and rare earth oxide compound precursor powder. Alter that, ultrafine or nanoscale tungsten powder with particle size of 50˜500 nm is obtained through a process of calcination subsequent with hydrogen thermal reduction. Finally, the tungsten powder is subjected to ordinary compression molding and then conventional high temperature sintering. The trace rare earth oxide dispersion strengthened high performance fine grain tungsten materials prepared by this invention, its density is close to full density (98.5% or higher), its grain size is uniform and very fine (average in 5˜10 microns), and the rare earth oxides particles evenly distribute in tungsten intracrystalline or grain, boundary with particle size of 100˜500 nm.

This invention relates to a preparation method of rare earth oxide dispersion strengthened fee grain tungsten materials, the mass percent of the rare earth oxide is of 0.1-2%, and the rest ingredient is W. Weigh soluble rare earth salt and tungstate, dissolve into water to made into 50-100 g/L of rare earth salt solution and 150-300 g/L of tungstate solution, respectively. Firstly, add trace alkali in rare earth salt solution to control pH in 7-8, then add organic dispersant and stir to form evenly suspended R(OH).sub.3 particle colloid (R refers to rare earth element). Secondly pour the tungstate solution into the R(OH).sub.3colloid, add trace acid to control pH in 6-7, then add organic dispersant and stir to form tungstic acid micro particles, which wrap around the colloidal particles, forming coprecipitation coating particle colloid. Thirdly, the coprecipitation coating particle colloidal is spray-dried, forming tungsten and rare earth oxide compound precursor powder. Alter that, ultrafine or nanoscale tungsten powder with particle size of 50˜500 nm is obtained through a process of calcination subsequent with hydrogen thermal reduction. Finally, the tungsten powder is subjected to ordinary compression molding and then conventional high temperature sintering. The trace rare earth oxide dispersion strengthened high performance fine grain tungsten materials prepared by this invention, its density is close to full density (98.5% or higher), its grain size is uniform and very fine (average in 5˜10 microns), and the rare earth oxides particles evenly distribute in tungsten intracrystalline or grain, boundary with particle size of 100˜500 nm.

A samarium-iron-nitrogen alloy powder according to one embodiment of the present invention is characterized in that a value obtained by dividing the hydrogen content of the samarium-iron-nitrogen alloy powder by the BET specific surface area of the samarium-iron-nitrogen alloy powder is less than or equal to 400 ppm/(m.sup.2/g), and a value obtained by dividing the oxygen content of the samarium-iron-nitrogen alloy powder by the BET specific surface area of the samarium-iron-nitrogen alloy powder is less than or equal to 11,000 ppm/(m.sup.2/g).

A samarium-iron-nitrogen alloy powder according to one embodiment of the present invention is characterized in that a value obtained by dividing the hydrogen content of the samarium-iron-nitrogen alloy powder by the BET specific surface area of the samarium-iron-nitrogen alloy powder is less than or equal to 400 ppm/(m.sup.2/g), and a value obtained by dividing the oxygen content of the samarium-iron-nitrogen alloy powder by the BET specific surface area of the samarium-iron-nitrogen alloy powder is less than or equal to 11,000 ppm/(m.sup.2/g).