The present invention provides a surface coating of SiC particles of tungsten methods. Specific steps are as follows:

1)Put the concentration of SiC particles into 70% nitric acid, and ultrasonic vibration to its roughened, removed after 5 minutes and rinsed with deionized water to obtain a clean and rough surface of SiC particles having;

2) The following ingredients and method of preparation of sol: Take 0.5-1 grams per 2.5-5 ml of tungsten powder and hydrogen peroxide reaction, the reaction after adding 2 ml of anhydrous ethanol and 0.75 ml of acetic acid mixed, filtered the reaction residue to give a pale yellow sol; sol to the amount formulated to meet the needs of the next step is completely submerged SiC ceramic particles;

3) The roughened treated SiC ceramic particles immersed in said sol, supplemented sonication for 10-20 minutes, so that a uniform dispersion of SiC particles in the sol;

4) SiC ceramic particles after the above process is placed in the 300-350 ℃ drying oven for 2-3 hours, then cool;

5) The above reducing the dried particles of SiC under a hydrogen atmosphere at 760-800 ℃ 2-3 hours, removed after the furnace with cooling to obtain a SiC ceramic coated tungsten particles.

The present invention is simple to operate, low cost, can be applied to not only SiC, Al2O3 ceramic and graphite particles, but also to the surface of any shape made ​​of these materials plated tungsten ceramic processing device.


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The present invention describes a rare earth - Ni - Mo - P - tungsten alloy plating solution formula to solve the electroless plating - nickel - molybdenum - phosphorus alloy technology exists bath temperature is high, poor stability, chemical deposition rate is low, microhardness small issues;

Formulations of the present invention include nickel chloride / nickel sulfate, sodium hypophosphite, sodium molybdate, rare earth, tungsten carbide, sodium citrate / citric acid, glycolic acid / sodium glycolate, succinic acid, boric acid, sodium hydroxide / sodium carbonate, thiourea, sodium dodecylbenzenesulfonate, a cathode current density Dk is 0.05 ~ 2.5, pH 7.0 to 8.5 at a temperature (T) of 30 ~ 65 ℃, anode nickel plate or platinum electrodes inert electrodes, cathode plating plating.

The temperature of the plating solution of the present invention significantly lower than the electroless plating solution, good stability, the deposition rate increased significantly, and easy to control, the plating solution of the present invention can be widely used in the plating process.
RE - Ni - Mo - P - Tungsten Alloy Plating Solution

Tungsten chemical on atomic layer deposition method of vapor deposition

The present invention provides a chemical vapor deposition method for atomic layer deposition of tungsten. Specific steps are as follows:

A) Using a first reaction gas chemical vapor deposition process to form a first reaction gas atoms deposited layer;

B) The effect of residual gas finished first reaction gas extraction;

C) A second reaction gas containing tungsten chemical vapor deposition process to form a gas phase to the second atomic layer deposition comprising the first reaction gas tungsten atomic layer deposition reaction;

D) The role of the second reaction gas tungsten finished pumping the remaining gas;

E) Repeat the above step A to D at least one step of forming cycle;

F) In the cycle, the select part of the cycle repeated in step C and D at least once.Tungsten Chemical on Atomic Layer Deposition Method of Vapor Deposition
 

The present invention is to introduce a tungsten carbide - steel gradient resistant materials.

Resistant materials can form gradients infiltrated tungsten carbide into steel (WC) by high-energy ions.

Currently on the market of high-chromium steels, cast stone and other wear-resistant surfacing materials present WC short life, the shortcomings of hardness, strength, toughness.

The invention form WC on the carbon or alloy steel surface on discharge principle. WC hardened layer ≥ 0.8mm, which WC rich layer over 0.3mm. WC - steel wear resistant materials gradient performance is usually hardened alloy tool steel 4 to 15 times, and has integrated high performance hard, high strength, high toughness, etc., which meets the technical requirements of many anti-wear conditions.
 

The present invention describes a tungsten / copper graded material. Characterized in that:

1) Material Design: both ends of the W / Cu graded materials are W and Cu alloys, the volume of distribution of the gradient layer W by the formula C = (x / d) p calculated, where: C is the volume of any gradient layer W percentage, x is the position of the layer corresponding to the gradient, d is the thickness of the graded layer, p is the composition distribution index, p values ​​in the range of 0.6-1.8;

2) the thickness of the metal layer W 1-4mm, the thickness of the metal Cu 1-2mm;

3) layers of the intermediate layer is 1-8 layers; in order to improve the bonding strength between the W-Cu, 5-10 weight percent of added copper in the metal binder phase, these adhesives are Ni, Zr, V , Ti and Cr.
 

The present invention provides a vacuum evaporation of tungsten oxide gas process for preparing a photochromic film. Specific steps are as follows:

1) cleaning the substrate;

2) The tungsten trioxide powder or pressed powder into vacuum chamber by electron beam evaporation crucible, a platinum resistance wire heating source on and fixed to the cleaning of the substrate in the sample holder;

3) use the electron beam heating of the tungsten trioxide in the sublimation and deposited on the substrate. Vacuum coating machine vacuum chamber pressure of 10-2 ~ 10-3Pa, vacuum chamber temperature of about 200-300 ℃, electron beam 0.1-0.2mA;

4) a layer of a platinum catalyst  deposited by resistance heating. Vacuum chamber pressure 5-6.5 × 10-3Pa, the chamber temperature is 200 - 300 ℃, steam barrier between the current 120-245A.

The present invention has a low cost, simple, good film quality, uniformity, color response time is short and so on.
 

The present invention provides a method for the manufacture of flame spraying of cobalt bonded tungsten carbide powder. Characterized in that:

1) Preparation of particles consisting essentially of -5 micron tungsten carbide powder having a first, a particle size of -44 +10 microns, a second tungsten carbide powder, the particle size of -5 microns and a particle size of the cobalt powder to 1 m carbon a powder mixture consisting of;

2) Ratio of the mixture was about 10 to 30% first tungsten carbide, 40 to 80% second tungsten carbide, 8 to 25% cobalt and 0.5 to 3% of carbon (a total of 100% by weight meter), and by compressing the mixture to produce a compressed product, the compressed product is sintered to produce a sintered product, crushing the sintered product to produce a crushed product, and classifying the pulverized product to produce the cobalt bonded tungsten carbide powder mixture to be processed.
 

The present invention describes a high iron-cobalt alloy of tungsten and molybdenum. Characterized in that:

Tungsten, molybdenum, cobalt source, the source component is cobalt (37-45%), tungsten (28-35%), molybdenum (25-35%), the use of double glow plasma surface alloying technology or other surface metallurgy technology low carbon steel, pure iron, high carbon steel or low alloy steel substrate surface to form an alloy of iron, tungsten, cobalt, iron, molybdenum, cobalt or iron, tungsten, molybdenum, cobalt alloy layer is high.

The surface of the alloy composition range of the surface layer is cobalt (18 to 30%), tungsten (9 to 20%), molybdenum (5-15%) remainder Fe;

Iron, then tungsten, molybdenum, cobalt-based alloy surface hardening alloying, solution, aging skin and tissue were distributed among the base metal alloy ferritic compounds, carbon alloy martensite and a small amount of residual austenite between the body portion and the undissolved metal compound deposited between the tempered martensite and a large original fine intermetallic compound and the metal compound, the type of tissue lining the undissolved selected by different substrates.
 

The present invention provides a use of tungstate scheelite ore production methods. Specific steps are as follows:

1) Prepare a slurry: First scheelite ore powder, hydrochloric acid and water were added to the slurry preparation tank, mixing, under conditions of 40 ~ 50 ℃ at room temperature or heated to the specific gravity of the slurry was adjusted to 1.15 to 1 .30, adjusted to an acid value of 110 ~ 130g / L;

2) The electrochemical decomposition treatment: after deployment good electrochemical reactor slurry input, namely the electrodes pass into 2 ~ 6V, the current density of DC volume of 300 ~ 1000A/m3 in the feed solution under stirring decomposition treatment 1 to 2 hours to a final acid value of 20 ~ 40g / L, a mixture of CaCl2 and H2WO4 containing feed solution;

3) Wash the filter: B prepared by mixing liquid input filter, and pass into the hot water washing, filtration, that was solid tungsten acid products.

Since the invention based on the traditional acid decomposition method based on the increase pass into direct current, at low temperatures of ore electrochemical treatment process, greatly improving the efficiency of the decomposition of scheelite, hydrochloric acid consumption reduced by more than half to reduce production costs 50%, an increase of productivity / 3. Thus with hydrochloric acid consumption is low, the reaction can be carried out at room temperature even lower, both to avoid volatilization of hydrochloric acid and air pollution, but also greatly reduces the workload and processing costs of wastewater treatment; environmental pollution and improve productivity, reduce production costs and other characteristics. To overcome the conventional acid decomposition excess of hydrochloric acid to be added and reacted at a high temperature state, both air pollution, waste water and high acid number, the processing workload, the productivity is low, production costs are high and other ills.

 

The invention belongs to the field of transparent conductive thin film technology, in particular to introduce a tungsten-doped tin dioxide (SnO2: W) polycrystalline tungsten-doped tin oxide transparent conductive oxide films. Characterized in that:

In the present invention, the metal tungsten powder and tin dioxide mixed by grinding, tabletting, the obtained sintered block material as a target; on a quartz glass substrate at room temperature using pulsed plasma deposition (PPD) technology, the appropriate target composition, deposition pressure, pulse current, pulse voltage, and the preparation obtained after the heat treatment technology SnO2 having a polycrystalline structure: W film.

Preparation of films having a low resistivity, excellent optical and electrical characteristics of high carrier mobility, the visible range (400-700nm) high transmittance and near infrared range (700-2500nm) high transmittance and the like. Film obtained in the method of the invention of flat panel display, photoelectric sensors, infrared sensors, and especially in the past in areas such as solar cells have good prospects.