95 results about "Internal oxidation" patented technology

The invention discloses a method for separating and recycling a silver-copper composite material through selective interface oxidation. The method comprises the following steps that the material is crushed and sheared, and a crushed material is obtained; the crushed material is pretreated and then fed into an oxidation fluidized bed, an internal oxidation reaction is conducted in a gas phase at the temperature of 400-700 DEG C and the oxygen pressure of 0.2-0.6 MPa, the reaction time is 20-60 h, and a high-temperature material is obtained; quenching the high-temperature material to generate stress cracks on an oxidation interface to obtain a cooled material; and stripping the cooled material under the mechanical action to obtain a recycled copper material and a recycled silver material, oxidizing the electrical contact material or leftover materials of the electrical contact material in the oxygen atmosphere to oxidize an interface between the silver-copper composite materials to form an oxidation film, separating the two materials of the silver-copper composite materials under the quenching and mechanical actions, and then, obtaining the recycled copper material and the recycled silver material. The method is high in recovery rate, high in recovery purity and environment-friendly.

The invention discloses a high-strength and high-plasticity copper alloy and a preparation method thereof. The high-strength and high-plasticity copper alloy is prepared by mixing Cu-Al pre-alloyed spherical powder and CuO powder according to the mass ratio of (100-150): 1, wherein the Cu-Al pre-alloyed spherical powder and the CuO powder are different in particle size range. The solid solution state Al element part in the high-strength plastic copper alloy is oxidized into Al2O3 through CuO, and the Al2O3 exists in a Cu matrix. The preparation method comprises the following steps: (1) mixing Cu-Al pre-alloyed spherical powder with CuO powder, and drying; (2) cold isostatic pressing treatment; (3) vacuumizing, sintering at a high temperature in a protective atmosphere, and cooling; (4) vacuumizing, reducing in a reducing atmosphere, and cooling; and (5) after preheating, the copper alloy reduction blank is placed in a rotary forging die, rotary forging and air cooling are conducted, and the copper alloy is obtained. The high-strength plastic copper alloy is good in conductivity and mechanical property and high in plasticity. The method is simple in process, environmentally friendly, low in cost and suitable for industrial production.

The application relates to a method for improving a tungsten-copper connecting interface based on internal oxidation and hydrogen reduction process, and relates to the technical field of tungsten-copper composite material preparation. First, an oxide (Cu2O, CuO) or oxygen is added to the surface of a tungsten block for internal oxidation treatment, a nano-oxide porous structure is generated on the surface, the surface roughness is increased, then hydrogen reduction is performed to remove surface oxide impurities, the surface pores are reserved, finally, the tungsten block with the treated surface is combined with copper powder through discharge plasma sintering to realize effective combination between tungsten and copper. Through the internal oxidation process, the influence of a metal alloy layer formed by a heterogeneous element brazing filler on the tungsten-copper interface compatibility and stability under radiation can be effectively avoided, and through the reduction treatment of high-purity hydrogen, the high-purity of the matrix is maintained, and the combination performance of the porous structure reinforced connecting layer is generated.

The purpose of the present invention is to provide a grain-oriented electrical steel sheet which does not have a forsterite coating film (glass coating film), and which has excellent iron loss that has been subjected to heat-resistant magnetic domain control. This grain-oriented electrical steel sheet has no forsterite coating film on the surface of a base steel sheet, is provided with a tension coating film (insulating coating film), has a plurality of grooves in the surface, and has an SiO2 intermediate layer and an insulating coating film in this order on the surface of the steel sheet, and the coating film tension of the tension coating film is 10 MPa or more. Furthermore, an SiO2 internal oxide layer is provided directly below the surface of the base steel sheet, and the irregularities between the surface of the steel sheet and the internal oxide layer are 0.001 [mu] m-0. 100 [mu] m.

Provided is a zinc plated steel sheet having excellent spot weldability and a manufacturing method thereof. The zinc plated steel sheet includes a steel sheet and a zinc plated layer formed on the surface of the steel sheet, wherein the ratio (a / b) between a widthwise average value (a) of thickness of an internal oxidized layer and a widthwise standard deviation (b) of thickness of the internal oxidized layer in the steel sheet may be 1.5 or more.

The invention relates to the technical field of alloy powder preparation, discloses high-entropy alloy powder and a preparation process thereof, and aims at solving the problems that Y2O3 particles are easy to agglomerate, the process depends on experience and the batch stability is poor in a traditional ODS high-entropy alloy process, a preparation method combining multi-scale simulation with digital twinning optimization is constructed, critical ball milling impact energy is simulated through molecular dynamics, and the high-entropy alloy powder is obtained. The method comprises the following steps: judging a ball milling end point in real time by adopting an acoustic emission intelligent monitoring system, and performing internal oxidation in an Ar-(3-10)% O2 atmosphere by utilizing defect engineering to generate Y2O3 nano-phase particles of 5-10nm; monitoring an O + / Ar + spectral line intensity ratio through a fiber optic spectrometer in SPS sintering to intelligently trigger pressure loading; constructing a digital twinborn body to realize virtual iterative optimization; the yield strength of the prepared high-entropy alloy powder reaches 1200-1300 MPa, the ductility is larger than or equal to 12%, and the strength is improved by 20-30% compared with that of a traditional process.

A hot-dip galvanized steel sheet according to one aspect of the present invention comprises a base steel sheet and a hot-dip galvanized layer formed on the surface of the base steel sheet, wherein the difference between the average of the Mn / Si values of surface oxides present on a surface portion, which is the region from the interface between the hot-dip galvanized layer and the base steel sheet to a depth of 15 nm, and the average of the Mn / Si values of internal oxides, which are present in the region from the interface to a depth of 50-100 nm, can be 0.5 or more. Mn and Si of each oxide mean the amounts (wt %) of Mn and Si components in the oxide, which are measured by EDS, and the average of Mn / Si values means the averaged value of the Mn / Si values measured for each oxide.

The application discloses a high-surface-quality 980MPa-grade hot-dip galvanizing DH steel and a preparation method thereof. The main chemical component mass content of the hot-dip galvanizing DH steel is as follows: C: 0.17-0.21%, Si: 0.4-0.7%, Mn: 1.8-2.2%, Nb: 0.01-0.02%, Ti: 0.01-0.02%, Cr: 0.4-0.5%, and Als: 0.14-0.9%. The method adopts low-carbon design and high-dew-point annealing process to produce the hot-dip galvanizing steel plate which meets the low-carbon environmental protection requirement and has high surface quality, so as to meet the urgent needs of the market. The high-dew-point annealing process is a new type of annealing technology, the oxygen partial pressure is increased by increasing the dew point, the Si and Mn element internal oxidation is realized, and thus the plating leakage defect is effectively improved, and the surface smoothness and flatness of the steel plate are improved.

The application discloses a preparation method of a multistage coating oxygen-mediated annealing based on RAFM steel / titanium nitride, and belongs to the technical field of coating preparation. The application method comprises the following steps: depositing a TiN coating on the surface of a low-activated ferrite / martensite steel base by using a magnetron sputtering, using a pure titanium target, and setting the nitrogen / argon flow ratio to 1:13-1:18, the base vacuum degree to 4-6*10 ‑5 Pa, and the deposition time to 60-90 min, and not applying additional active heating to the base during the deposition process; packaging the deposited coating sample in a quartz tube, providing a trace oxygen atmosphere in the tube by means of the gas pressure in the tube; and then performing 800-1000 DEG C annealing treatment and keeping the temperature for 90-120 min. Through oxygen-mediated element diffusion and reaction, a multistage composite structure, which comprises, from the base outward, an internal oxidation layer, an Fe internal enrichment layer, a TiN layer, an Fe external enrichment layer and an external oxidation layer, is formed in the TiN coating in situ. The application method is simple in process, does not need to deposit a transition layer additionally, the prepared multistage coating is well combined with the base, has excellent thermal shock resistance, and can withstand more than 30 times of thermal shock cycles.

The alloyed hot-dip galvanized steel sheet of the present disclosure has a base steel sheet having a prescribed chemical composition in mass%, and a plated layer, and the existence ratio ER of a specific internal oxide is 40% or less and the interval I of the internal oxide is 300 μm or more when a cross section of the base steel sheet is observed under prescribed conditions. The alloyed hot-dip galvanized steel sheet of the present disclosure is excellent in appearance and the like.

This invention relates to a clad steel sheet and a method for manufacturing the same. The clad steel sheet comprises: a base steel sheet, which, by weight percent, contains: C: 0.10-0.25%, Mn: 1.5-5.0%, Si: 0.5-2.5%, Cr: less than 1.5%, Al: 0.005-0.100%, P: less than 0.10%, S: less than 0.020%, B: less than 0.0050%, with the balance being Fe and other unavoidable impurities; and a coating formed on at least one side of the base steel sheet, wherein, with reference to the direction from the interface between the base steel sheet and the coating toward the thickness center, the depth of the internal oxide layer composed of one or more oxides of Mn, Si, Cr and B is 3-15 μm. More specifically, the invention relates to a clad steel sheet with excellent surface quality and weld LME resistance, and a method for manufacturing the same.

High strength plated steel sheet having high hydrogen embrittlement resistance, that is, alloyed hot dip galvannealed steel sheet including steel sheet containing C: 0.05 to 0.40%, Si: 0.2 to 3.0%, Mn: 0.1 to 5.0%, and sol. Al: 0.4 to 1.50% and a alloyed hot dip galvannealed layer deposited on at least one surface of the steel sheet to 10 to 100 g / m2 and containing Fe: 5.0 to 15.0% and Al: 0.01 to 1.0%, having an internal oxidation layer including grain boundary oxides in a surface layer of the steel sheet, when examining a cross-section of a surface layer of the steel sheet, a Ratio A of the length of the grain boundary oxides projected an interface of the steel sheet and the alloyed hot dip galvannealed layer to the length of interface is 50% or more and 100% or less, and a surface depleted layer with a steel composition not including the grain boundary oxides which satisfies, by mass %, Si≤0.6% and Al≥0.05% is included at a depth of ½ of the average depth of the internal oxidation layer.

To provide an Fe-based electroplated steel sheet that not only has excellent chemical convertibility or excellent coating appearance when subjected to hot-dip galvanizing, but also has excellent resistance to cracking in resistance welding. Disclosed is an Fe-based plated steel sheet including: a cold-rolled steel sheet having a chemical composition containing Si in an amount of 0.1 mass % or more and 3.0 mass % or less; and an Fe-based electroplating layer formed on one or both surfaces of the cold-rolled steel sheet with a coating weight per surface of 1.0 g / m2 or more, in which a thickness of an internal oxidation layer is 2.00 μm or less, and an average value of C concentration in a range of 10 μm to 20 μm in a thickness direction from the surface of the Fe-based electroplating layer is 0.10 mass % or less.

The invention belongs to the technical field of alloy manufacturing, and particularly relates to a low-deformation ultrahigh-temperature electrothermal alloy and a preparation method thereof. Compared with a single-powder single-oxygen idea in the prior art, the scheme has the advantages that double powder-double chemical potential gradient is used for driving secondary dispersion precipitation for the first time, the side effect of'shell caused by excessive oxygen 'is converted into an'internal oxygen source', the inherent contradiction between agglomeration of an external addition method and insufficient gradient of an internal oxidation method is overcome, a continuous and controllable causal chain is formed, and the method is suitable for industrial production. And finally, the strength-service life bottleneck of the 1400 DEG C grade FeCrAl electrothermal alloy is solved.

The invention discloses an oxide dispersion strengthened copper alloy stranded wire and a preparation method thereof, and belongs to the technical field of copper-based composite materials and powder metallurgy, the alloy components comprise, by mass, 0.15%-0.55% of Al, 0.03%-0.15% of Y, 0.01%-0.06% of Ti and the balance Cu, Al2O3 and Y3Al5O12 composite dispersed phases are dispersed and distributed in a matrix, and the composite dispersed phases are dispersed and distributed in the matrix. The preparation method comprises the steps of gas atomization powder preparation, gradient oxygen partial pressure internal oxidation, hydrogen reduction, cold isostatic pressing, hot extrusion, cold drawing, stranding and stable annealing, the tensile strength of the stranded wire is not lower than 500 MPa, the electric conductivity is not lower than 82% IACS, and the strength retention rate is not lower than 90% after heat preservation at 800 DEG C for 100 h.

To provide a high-strength steel sheet and a plated steel sheet having high plating property, liquid metal embrittlement (LME) resistance, and hydrogen embrittlement resistance. There is provided a steel sheet and a plated steel sheet using the same, the steel sheet containing C: 0.05 to 0.40%, Si: 0.2 to 3.0%, Mn: 0.1 to 5.0%, and sol.Al: 0.4 to 1.50%, and having an internal oxide layer containing fine granular oxides, coarse granular oxides, and grain boundary oxides in the surface layer of the steel sheet. The number density of the fine granular oxides in the internal oxide layer is 4.0 particles / μm 2 or more, the number density of the coarse granular oxides in the internal oxide layer is 4.0 particles / 25 μm 2 or more. When observing the cross-section of the surface layer of the steel sheet, the ratio A of the length of the grain boundary oxides projected onto the surface of the steel sheet to the length of the surface of the steel sheet is 50% or more and 100% or less. The surface layer of the steel sheet contains a surface layer depletion layer, and the steel composition without oxides at a depth of 1 / 2 of the average depth of the internal oxide layer calculated from the cross-section SEM image of the steel sheet satisfies Si ≤ 0.6% and Al ≥ 0.05% by mass.

The invention belongs to the technical field of diamond copper composite materials, and particularly relates to a preparation method of a high-strength and high-thermal-conductivity copper-based composite material and the high-strength and high-thermal-conductivity copper-based composite material. The preparation method of the high-strength and high-thermal-conductivity copper-based composite material comprises the following steps that (1) diamond particles and copper-aluminum alloy powder are mixed and then subjected to heat treatment in an inert atmosphere, and diamond-copper mixed powder is obtained; and 2) mixing the diamond-copper mixed powder obtained in the step 1) with an oxygen source, performing compression molding, and performing internal oxidation reduction sintering. Aluminum carbide and Cu-Al-C are generated on the surface of diamond in situ through interface reaction to improve the interface bonding strength of the diamond and a copper matrix, Al2O3 nanoparticles are generated in situ through internal oxidation-reduction-sintering, the interface bonding capacity and the heat conduction performance are further improved, and then preparation of the high-strength and high-heat-conduction copper-based composite material is achieved.

The present application belongs to the field of electrical materials and powder metallurgy, and particularly relates to a preparation method of a high-voltage electric contact with gradient tungsten-copper alloy and dispersion-strengthened copper composite. The W90Cu / W70Cu / W50Cu gradient layer is prepared by adopting gradient porosity pre-preparation and integrated pressing infiltration technology; the ODS-Cu matrix is prepared by adopting accurate internal oxidation-reduction technology; the vacuum hot pressing-brazing composite connection technology is adopted, combined with pressure keeping in the cooling stage, and the high-temperature plastic rheology of the copper matrix is used to actively inhibit the residual thermal stress, so that the W-Cu / ODS-Cu interface shear strength is greater than or equal to 300 MPa. The contradiction between the ablation resistance, electrical conductivity, thermal stability and interface reliability of the contact material is solved, and the service performance and structural reliability of the high-voltage electric appliance are significantly improved.

The invention relates to the field of preparation of electric contact materials, and particularly discloses a silver tin oxide indium oxide electric contact material and a preparation method thereof. The method comprises the following steps: mixing Ag, Sn, In and AgMe, and carrying out vacuum induction melting to obtain an alloy solution; after casting the alloy solution, cooling and curing to obtain an alloy particle plant; preheating the alloy particles, and then carrying out an equal-pressure differential-temperature rapid internal oxidation process to obtain a crude product of the electric contact material; and carrying out post-treatment on the crude product of the electric contact material to obtain the electric contact material. According to the preparation method, a one-step granulation method is combined with an equal-pressure differential-temperature rapid internal oxidation process, so that the production period is greatly shortened, the oxidation speed is remarkably increased, the uniformity and compactness of an oxidation film are improved, and the prepared electric contact material has good electrical and mechanical properties.

The present invention relates to a plated steel sheet and a method for manufacturing same, the plated steel sheet comprising: a base steel sheet that contains, in wt%, 0.10-0.25% of C, 1.5-5.0% of Mn, 0.5-2.5% of Si, 1.5% or less of Cr, 0.005-0.100% of Al, 0.10% or less of P, 0.020% or less of S, and 0.0050% or less of B, with the remainder comprising Fe and inevitable impurities; and a plating layer formed on at least one surface of the base steel sheet, wherein the depth of an internal oxide layer composed of an oxide of at least one among Mn, Si, Cr, and B is 3-15 μm from the interface between the base steel sheet and the plating layer toward the middle of the plated steel sheet in the thickness direction. More specifically, the present invention relates to a plated steel sheet having excellent surface quality and welding LME resistance, and a method for manufacturing same.

A grain-oriented electrical steel sheet includes a base steel sheet and an insulation coating arranged in contact with the base steel sheet. When the grain-oriented electrical steel sheet is viewed in a cross section whose cutting direction is parallel to a thickness direction and perpendicular to a transverse direction, the base steel sheet includes an internally oxidized SiO2 within a range of 2.0 μm from an interface with the insulation coating toward a thickness direction.

The present invention discloses a method for preparing a spherical copper yttrium oxide powder with a coating structure, comprising the following steps: (1) vacuum melting; (2) vacuum gas atomization; (3) internal oxidation process; (4) high-temperature reduction; (5) field-assisted sintering. The present invention prepares a copper-yttrium alloy ingot into a copper-yttrium alloy powder by vacuum melting and vacuum gas atomization. The alloy powder obtained by this process is spherical and the yttrium is evenly distributed in the copper; Y is oxidized into Y2O3 by an internal oxidation and reduction process, and the excess CuO is reduced to Cu. The Y2O3 particles obtained by this process are fine and evenly distributed, and the ODS-Cu powder has good sphericity and excellent fluidity; the ODS-Cu bulk material prepared by the powder maintains a high hardness of more than 130HV and also has a high elongation of more than 50% and a high conductivity of 90% IACS that other ODS-Cu materials do not have.

The present invention provides a high-strength steel sheet having high platability, LME resistance, and hydrogen embrittlement resistance, and a plated steel sheet. A steel sheet and a plated steel sheet using the same are provided, the steel sheet including C: 0.05 to 0.40%, Si: 0.2 to 3.0%, Mn: 0.1 to 5.0%, and sol. Al: 0.4 to 1.50%, wherein an internal oxidation layer including fine-grained oxides is present in a surface layer of the steel sheet, the number density of the fine-grained oxides in the internal oxidation layer is 4.0 pieces / µm 2 In the above, the surface layer of the steel sheet includes a surface layer deficiency layer, the surface layer deficiency layer consisting of an oxide-free steel at a depth of 1 / 2 of the average depth of the internal oxidation layer calculated from a cross-sectional SEM image of the steel sheet, the oxide-free steel satisfying, in mass%, Si ≤ 0.6% and Al ≥ 0.05%.

A galvanized steel sheet comprising a steel sheet containing C: 0.05 to 0.30%, Si: 0.01 to 3.00%, Mn: 0.80 to 3.00%, and Al: 0.010 to 2.000% and having a thickness of 0.10 to 0.95 mm, and a galvanized layer on the steel sheet, wherein a tensile strength is 550 to 1500 MPa, and, when defining a thickness of an internal oxide layer per surface of the steel sheet as “A” (μm), a thickness of a decarburized layer per surface of the steel sheet as “B” (μm), and a thickness of the steel sheet as “t” (μm), A / B: 0.01 to 0.50 and B / t: 0.001 to 0.200.

One embodiment of the present invention provides: a high toughness high carbon cold rolled steel sheet having excellent formability comprising, by weight %, C: 0.80% to 1.25%, Mn: 0.2% to 0.6%, Si: 0.01% to 0.4%, P: 0.005% to 0.02%, S: 0.01% or less, Al: 0.01% to 0.1%, Cr: 0.01% to 1.0%, Sn: 0.05% to 0.5%, the remainder being Fe and other unavoidable impurities, in which a microstructure includes, by area %, retained austenite: 1% to 10%, martensite: 1% to 10%, ferrite: 5% or less (including 0%), the remainder being bainite, and has an average grain size of 3 μm to 20 μm, and an internal oxide layer formed directly below the surface has a thickness of 10 μm or less; and a method for manufacturing same.

The present invention addresses the problem of providing a plated steel sheet having excellent LME resistance and red rust resistance. This plated steel sheet is provided with a plating layer on one or both surfaces of a steel sheet, and has a tensile strength of 780 MPa or more, the steel sheet having a prescribed chemical composition, the plating layer containing Zn, and the thickness of the plating steel sheet in a GDS measurement in the thickness direction of the plated steel sheet being greater than or equal to 100 [mu] m. A depth at which the luminous intensity Bx at a depth x ([mu] m) and the luminous intensity B150 at a depth 150 [mu] m satisfy Bx / B150 > = 5.0 is 0.5 [mu] m or more from the interface between the steel sheet and the plating layer, the thickness of the oxide formed on the surface of the plating layer is 0.5 [mu] m or less, and an internal oxide layer having a thickness of 1.0 [mu] m or more is present in the thickness direction of the steel sheet from the interface.

The invention discloses a graphene and aluminum oxide synergistically reinforced copper-based composite material and a preparation method thereof, and belongs to the technical field of metal-based composite material preparation. According to the method, dispersed nano-particles are formed in a copper matrix through internal oxidation-reduction, the surface is removed through selective pickling, a pure copper surface layer is exposed, then the surface of powder is coated with high-quality graphene through a CVD technology, and then the high-performance composite material is obtained through cold isostatic pressing, protective atmosphere sintering and hot extrusion densification. According to the composite material, 10-50 nm particles are distributed in a dispersed mode, graphene is of a 1-5-layer structure, the density is larger than or equal to 99.2%, the tensile strength ranges from 365 MPa to 485 MPa, the conductivity ranges from 78% to 92% IACS, and collaborative optimization of the strength and the conductivity is achieved. The preparation method is suitable for large-scale production and can be widely applied to the fields of electric power, electronics, rail transit and the like.

The purpose of the present invention is to provide a resistance spot welding method and a method for manufacturing a welded member. The present invention is a resistance spot welding method in which a plate group in which two or more steel plates are stacked is sandwiched by a pair of welding electrodes and energized while being pressurized to join the steel plates to each other, the resistance spot welding method comprising a holding step in which the welding electrodes are held after the energization is completed, the pressure holding time is controlled so as to be within a prescribed time range defined by a specific relational expression using the C content, Si content, and Mn content of the steel sheet, and the decarburized layer thickness and internal oxidation amount of the surface layer of the steel sheet.

This invention belongs to the field of metallurgical technology, and particularly relates to a low-cost, high-surface-quality galvanized hot-formed steel sheet production method. It includes the following steps: S1, using hot-rolled steel strip as raw material, controlling the coiling temperature of the hot-rolled steel strip to ≤550℃ through segmented laminar flow cooling; S2, pickling the hot-rolled steel strip using a composite pickling solution; S3, continuously galvanizing the pickled hot-rolled steel strip, wherein the heating temperature before galvanizing is ≤600℃. This invention eliminates the cold rolling and high-temperature annealing processes, fundamentally avoiding the internal oxidation defects of high-alloy hot-formed steel. The resulting steel sheet has a smooth surface without pitting or incomplete coating, and the interface between the coating and the substrate is clear and uniform. Simultaneously, the composite pickling solution improves pickling efficiency and reduces HCl volatilization. This invention has advantages such as low cost, high surface quality, and strong alloy adaptability.

The present application relates to a kind of pre-sand grinding processes of large particles, specifically including the following steps: step one: by using crusher, large oxide particles are broken;Step two: by water injection device, the oxide particles are dispersed with water;Step three: the oxide particles after being dispersed with water are transported to pre-sand grinding device and broken to specified size, then output;Step four: the oxide particles meeting the specified size are put into sand mill and ground into oxide powder;After two driving rollers pass through the two corners of the crushing box, the crushing box moves downward due to gravity, collides with the support plate to generate vibration, changes the position and angle of the oxide particles in the crushing box, and by controlling the reciprocating extension of the extension end of the hydraulic cylinder, the oxide particles in the crushing box are crushed multiple times, so that the particle size of the internal oxide particles meets the requirements, and the crushing efficiency of the oxide particles is improved.