The invention relates to a method for preparing high-melting-point metal powder through multi-stage deep reduction, and belongs to the technical field of preparation of powder. The method includes the following steps of mixing dried high-melting-point metal oxide powder with magnesium powder and performing a self-propagating reaction, placing an intermediate product into a closed reaction kettle, leaching the intermediate product with hydrochloric acid as a leaching solution so as to obtain a low-valence oxide Me.sub.xO precursor of the low-valence high-melting-point metal; uniformly mixing the precursor with calcium powder, pressing the mixture, placing the pressed mixture into a vacuum reduction furnace, heating the vacuum reduction furnace to 700-1200° C., performing deep reduction for 1-6 h, leaching a deep reduction product with hydrochloric acid as a leaching solution and performing treatment, so as to obtain the high-melting-point metal powder.

The invention relates to a method for preparing high-melting-point metal powder through multi-stage deep reduction, and belongs to the technical field of preparation of powder. The method includes the following steps of mixing dried high-melting-point metal oxide powder with magnesium powder and performing a self-propagating reaction, placing an intermediate product into a closed reaction kettle, leaching the intermediate product with hydrochloric acid as a leaching solution so as to obtain a low-valence oxide Me.sub.xO precursor of the low-valence high-melting-point metal; uniformly mixing the precursor with calcium powder, pressing the mixture, placing the pressed mixture into a vacuum reduction furnace, heating the vacuum reduction furnace to 700-1200° C., performing deep reduction for 1-6 h, leaching a deep reduction product with hydrochloric acid as a leaching solution and performing treatment, so as to obtain the high-melting-point metal powder.

The present invention belongs to the technical field of preparation of light metal alloy materials, in particular to a method for producing a magnesium-lithium alloy by a gaseous co-condensation method. The method comprises the steps of: 1) mixing and briquetting a lithium salt, a refractory agent and a catalyst under pressure, and then thermally decomposing to form an unsaturated composite oxide; 2) respectively crushing and ball-milling, and then briquetting the unsaturated composite oxide, magnesium oxide, a reducing agent and a fluxing agent; 3) reducing briquettes in vacuum; 4) making a gas pass through a first condensing chamber of a temperature control device, and then purifying; 5) The purified metal gas is condensed into the condensing phase of the alloy through the second condensing chamber of a quenching device; 6) obtaining the magnesium-lithium alloy with a purity being 99.5% or above by virtue of smelting and flux-refining, and then purifying by distillation. The magnesium-lithium alloy obtained in the present application is not segregated, so that a stable β-phase solid solution or a compound having an increasing purity being 99.95% is formed.

The present invention belongs to the technical field of preparation of light metal alloy materials, in particular to a method for producing a magnesium-lithium alloy by a gaseous co-condensation method. The method comprises the steps of: 1) mixing and briquetting a lithium salt, a refractory agent and a catalyst under pressure, and then thermally decomposing to form an unsaturated composite oxide; 2) respectively crushing and ball-milling, and then briquetting the unsaturated composite oxide, magnesium oxide, a reducing agent and a fluxing agent; 3) reducing briquettes in vacuum; 4) making a gas pass through a first condensing chamber of a temperature control device, and then purifying; 5) The purified metal gas is condensed into the condensing phase of the alloy through the second condensing chamber of a quenching device; 6) obtaining the magnesium-lithium alloy with a purity being 99.5% or above by virtue of smelting and flux-refining, and then purifying by distillation. The magnesium-lithium alloy obtained in the present application is not segregated, so that a stable β-phase solid solution or a compound having an increasing purity being 99.95% is formed.

The present invention relates to a method for producing a platinum-based alloy powder, the method comprising a heat treatment of a mixed powder containing a platinum-based powder composed of at least one selected from the group consisting of platinum and platinum compound, a platinum group metal-based powder composed of at least one selected from the group consisting of iridium, rhodium, palladium, and compound containing at least one of them, and an alkaline-earth metal compound, wherein specific surface area of the platinum group metal-based powder is 30 m.sup.2/g or more and D90 of the mixed powder is 1.0 μm or less. According to the method for producing a platinum-based alloy powder of the invention, it is possible to produce a platinum-based alloy powder that has a desired particle diameter, also has a sharp particle size distribution, and has high purity and crystallinity.

The invention relates to the rare metal smelting field, and particularly, the present invention relates to a tantalum powder for preparing capacitors and a process for preparing the tantalum powder, and to a sintered anode prepared from the tantalum powder. As to the tantalum powder as provided by the invention, its primary tantalum powder has a BET of from 3.0 to 4.5 m.sup.2/g. After the secondary agglomeration, the tantalum powder has a large particle size. The tantalum powder has an average Fisher sub-sieve size (FSSS) of 1.2 to 3.0 μm wherein as measured with a standard sieve mesh, more than 75% of tantalum powder has a +325-mesh, and a particle size distribution D50 of more than 60 μm, that is, the secondary particle size is high. A resultant capacitor anode prepared by sintering the tantalum powder of the invention at 1200° C. for 20 minutes and then being energized at the voltage of 20 V has the specific capacitance of from 140,000 to 180,000 μFV/g and the residual current of less than 1.0 nA/μFV. Meantime, the invention provides an economical process for making the tantalum powder.

The invention relates to the rare metal smelting field, and particularly, the present invention relates to a tantalum powder for preparing capacitors and a process for preparing the tantalum powder, and to a sintered anode prepared from the tantalum powder. As to the tantalum powder as provided by the invention, its primary tantalum powder has a BET of from 3.0 to 4.5 m.sup.2/g. After the secondary agglomeration, the tantalum powder has a large particle size. The tantalum powder has an average Fisher sub-sieve size (FSSS) of 1.2 to 3.0 μm wherein as measured with a standard sieve mesh, more than 75% of tantalum powder has a +325-mesh, and a particle size distribution D50 of more than 60 μm, that is, the secondary particle size is high. A resultant capacitor anode prepared by sintering the tantalum powder of the invention at 1200° C. for 20 minutes and then being energized at the voltage of 20 V has the specific capacitance of from 140,000 to 180,000 μFV/g and the residual current of less than 1.0 nA/μFV. Meantime, the invention provides an economical process for making the tantalum powder.

Aspects relate to method of zinc-comprising nanowire fabrication, the method comprising forming a starting material comprising zinc metal or zinc metal alloy and at least one reactive metal, and exposing the starting material to one or more alcohols to obtain a reaction product comprising zinc-comprising nanowires, wherein the at least one reactive metal is more reactive than zinc to the one or more alcohols.

Provided are an apparatus for manufacturing a compound powder, a method of manufacturing an iron-boron compound powder by using the apparatus, a boron alloy powder mixture, a method of manufacturing the boron alloy powder mixture, a combined powder structure, a method of manufacturing the combined powder structure, a steel pipe, and a method of manufacturing the steel pipe The method of manufacturing the boron alloy powder mixture includes: preparing a mixed powder including a boron iron alloy powder and a target powder; heat-treating the mixed powder to boronize at least a portion of the target powder and de-boronize at least a portion of the boron iron alloy powder, thereby de-boronizing the boron iron alloy powder to reduce the melting point of the boron iron alloy powder.

Provided are an apparatus for manufacturing a compound powder, a method of manufacturing an iron-boron compound powder by using the apparatus, a boron alloy powder mixture, a method of manufacturing the boron alloy powder mixture, a combined powder structure, a method of manufacturing the combined powder structure, a steel pipe, and a method of manufacturing the steel pipe The method of manufacturing the boron alloy powder mixture includes: preparing a mixed powder including a boron iron alloy powder and a target powder; heat-treating the mixed powder to boronize at least a portion of the target powder and de-boronize at least a portion of the boron iron alloy powder, thereby de-boronizing the boron iron alloy powder to reduce the melting point of the boron iron alloy powder.