Tungsten carbide rock drill buttons wear mechanisms have been the focus of numerous studies, and a large amount of wear data has been published. Recently a new, more comprehensive, view on the deterioration and wear mechanisms of cemented carbide rock drill buttons comes up. The new view combines some of most important aspects, including two life limiting factors, five classes of mechanisms of deterioration and five classes of material removal mechanisms. The view is based on careful high resolution investigations of worn tungsten carbide rock drill buttons selected from drilling of different rock types.

The deterioration includes a fundamental change of material and properties due to intermixing of rock material and cemented carbide in the surface layer of the button. It further includes corrosive decay and oxidation of WC and formation of large-scale cracks in a reptile skin pattern.



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Tungsten crucible sintering process:
Sintering in the medium frequency induction furnace, and the temperature is controlled at: 2200 ℃ -2250 ℃ around, and should be held 3h-5h. Thermal insulating once again in the middle-temperature phase, the control of temperature is around 1600 ℃ -1700 ℃, time thermal insulation is around 1.5h, so densification of product will be better . Moreover, heating temperature speed should not too fast, otherwise the crucible is easy to deform, and the temperature should be controlled at: 80℃-100℃around. Besides, the vacuum degree should be bigger than 0.67Pa when sintering.

In addition, through matting the same material tungsten plate at the bottom of the crucible or installing the furnace by proper way, and it will be possible to avoid the situation in which the sintering tungsten crucible bottom will crack, making the quality of tungsten crucible is guaranteed. By this sintering process, tungsten crucible density can reach to 17.3g / cm³ and above.


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Tungsten crucible, also called tungsten melting pot, which owns different types, such as, spinning molding type, sintering molding type, pressing molding type, welding molding type and the type made by car molding, and so on. Tungsten crucible working environment of temperature is above 2000℃.

Tungsten crucible application:
Thanks to tungsten’s high melting point, tungsten crucible, as a core container, is widely applied in sapphire growth furnace, single crystal furnace, quartz glass melting furnace, induction furnace, rare earth melting furnace and other furnaces. In the sapphire crystal growth furnace process, the following features of tungsten crucible will affect the success ratio of seed growth, quality and service life of sapphire crystal.

Tungsten crucible feature: high purity, high density, wear resistance, high melting, corrosion resistance, no crack and other features.

Tungsten crucible is also playing an important part in glass and ceramic manufacturing, powder metallurgy industry, machinery processing and other industries.


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Tungsten carbide flat button is the button with the flat top surface; it is mainly used for plating mine with the cone drills and gage with buttons. It has high wear resistance and toughness, high modulus of elasticity, high flexural strength and high chemically stability.

A variety of models and sizes of tungsten carbide flat buttons:

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Tungsten crucible can be divided into different types, pressing type of tungsten crucible, sintering type of tungsten crucible, welding type of tungsten crucible, spinning type of tungsten and the type made of tungsten rod by car molding processing.

Pressing tungsten crucible should choose appropriate tungsten powder grain size; in order to avoid the tungsten crucible will all be cracking in pressing process. Usually, if the tungsten powder grain size is too small, and the surface area is larger, and the contact area among ​powder is also large, so the displacement and deformation between tungsten powder will increase in pressing process, and the elastic coefficient will also increasing. It is likely to cause cracking of the tungsten crucible if the above situation happened and the stress is relaxed when pressing. If the selection of tungsten powder is too bigger, that is, tungsten powder grain size is too coarse, smaller than surface area; the contact area between the tungsten powders will reduce, so the tungsten crucible is too easy to crack after pressing due to its low density of compaction. Therefore, the choice of tungsten powder grain size range should be: about 2.5μm3.0μm. At the same time, special attention should pay to the control of oxygen content; it should be 0.1% or less.


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Tungsten carbide claws button is the button with the shape of claws. It is also called cemented carbide claws button.  Because of its high wear resistance, high bending strength and high hardness, tungsten carbide mushroom button is ideally suited for wear parts, other machine parts and dies which are subject to severe service conditions, such as high temperatures, corrosion and abrasion.

The following are the most common type of tungsten carbide claws buttons:

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The common feature of liquid phase method producing nano particles are basic on homogeneous phase solution, through a variety of ways to make the solute and solvent separation, so the solvent to form certain shape and size particles which is required precursor powder after pyrolysis will obtain nano particles. Liquid phase methods include precipitation method, microemulsion method, hydrolysis method, sol-gel method, hydrothermal method. Precipitation method has co-precipitation method and chemical precipitation.

Chemical precipitation is adding an appropriate precipitating agent in salt solution to obtain a ceramic precursor precipitate then calcined to form a nano-ceramic powder. For example, Using (NH4) 10W12O41 • 5H2O as raw materials prepare H2WO4 then after dehydration and calcination to obtain WO3 ceramic powder. At different temperatures (300 ~ 600 ℃) treatment, the resulting particle size range is 16 ~ 57nm. Or using APT as raw materials and prepared H2WO4, and then calcined to obtain WO3 ceramic powder. At 300 ~ 600 ℃ heat treatment conditions can be obtained powder particle size 16 ~ 57nm. Using chemical deposition method producing nano-particle size was more uniform than using pure APT after pyrolysis obtained powder particle.

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Tungsten trioxide is widely used in modern industry, not only development in gas-sensitive materials, electrochromic and other fields but also development and applied in catalysis which is also very extensive. And tungsten trioxide insoluble in water and acid, but in excess of H2O2 solution, since [O₂] ^2- has strong electronegativity will cause coordination interaction with WO3 forming an oxide tungstate (H₂ [W₂O₃ (O₂) ₄ (H₂O) ₂]) ^{11-12}. Reaction with oxide tungstate the cyclohexythanoids will turn into cyclohexanone. Oxide tungstate not only brings active oxygen but also brings acidity to reaction system. What’s more suitable acidity has for H₂O₂ oxidizing reaction has a strong catalytic effect.

When the amount of tungsten trioxide at 0.50mmol, the acidic of solution is lower, the active centers number less, and cyclohexanone yield is very low. With the tungsten trioxide dosage increased, acidity of the solution and the number of active centers are also increase. So product yield increased accordingly. When the amount of tungsten trioxide increased 1mmol, has been able to provide the number of active centers required for the reaction, cyclohexanone yield arrived at 73.5%, and increases the amount of tungsten trioxide, cyclohexanone yield no significant increase. That is unlimited increase in the amount of catalyst can not increase the yield of cyclohexanone.

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Using XRD-600 diffractometer analysis films structure and morphology which producing by different methods. Different forms of tungsten trioxide film were annealed at different temperatures.

After studies found films light transmittance is similar which produced by sol-gel method and magnetron sputtering method before annealing. the transmittance of thin film samples decreased after annealing at above 300 ℃, the light transmittance will reduce. Besides, annealing temperature more high the light transmittance will lower. Tungsten trioxide film are amorphous  which annealed at 350℃ below, within the range of 350 ~ 400 ℃ annealing, the amorphous film gradually complete transition to crystalline, annealing at 400 ℃ above, the substrate also had a diffraction peak. Morphology and optical properties of tungsten trioxide films have a great impact on its gas sensing properties, such as relatively porous amorphous film, which will help the adsorbed gas so the sensitivity of hydrogen may be higher than the crystalline structure of the film, so that the results of the study have some guidance on hydrogen Sensitivities.

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By comparing the magnetron sputtering method and sol-gel method producing tungsten trioxide films respectively found little difference in light transmittance. But the films producing by magnetron sputtering method the spectrum peaks and valleys more obvious that is the film producing by magnetron sputtering absorb different wavelengths light greater than the sol- gel method.

Analysis films transmission spectra which are producing by gel-sol method at different annealing temperatures before and after. Tungsten trioxide film producing by sol-gel method, the annealing temperature is higher, the lower the light transmittance of it. At 300℃ annealing for 30min, film transmittance fell by an average of 10%, peaks and valleys wavelength position will move to ultraviolet wave slightly which is not obvious. At 380℃ annealing transmittance of the film was reduced by 20% to 25%, and in the infrared portion the light transmittance decline rapidly, the peak number did not change, the difference between the peaks and troughs of the light transmittance becomes smaller. After annealing at 400 ℃ film transmittance decreased by 25% to 30%, and in the infrared portion the light transmittance decline was particularly pronounced.

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