When using one or more discrete bodies of polycrystalline diamond it was surprisingly found that the cracking and chipping tendency of tungsten carbide button considerably decreased. At the same time the wear resistance of the buttons was surprisingly high.

The explanation for these effects, the increase of the resistance against cracking and chipping and against wearing, might be a favourable stress pattern caused by the difference between the thermal expansion of the diamond body and the tungsten carbide body, giving the diamond a high and uniform compressive prestress.

A further improvement of the behavior of tungsten carbide buttons was revealed when using a tungsten carbide body having a multi-structure according to U.S. Pat. No. 4,743,515, it was surprisingly found that the cracking tendency of the tungsten carbide in the bottom of the bodies of polycrystalline diamond considerably decreased compared to the corresponding geometry and composition without the multi-structure carbide. Also the wear resistance of tungsten carbide buttons was improved at the same time.



Tungsten Carbide Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten-carbide.com.cn
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email:   sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn


 

Shank Sizes

The shank of tungsten carbide burs refer to the end of the bur that contacts with rotary tool. The popular shank sizes in markets including, 1.6mm, 2.35mm, 3mm and 6mm.

Shapes

The different shaped tungsten carbide burs could fit into different nook and cranny to generate distinctive profiles. Generally the burs shapes to be chose largely depend on the the profiles are aimed.

Speed

In terms of tungsten carbide burs’ rotary tools speed selection, the attention should be paid to the materials to be operated on and the forms being made. The recommended speed is within 35,000rpm. If the speed is too slow, the burs are easily to be fractured, whereas it is better to set up with slow speed and increasing the speed as the process going on. For the high speeds it could make effort in preventing clogging in the flutes.
 

Tungsten Carbide Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten-carbide.com.cn
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email:   sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn

Tungsten carbide bursare used to deal with cutting, shaping, grinding and removing the sharp edges, burs and excess material in practices and end mills for metalworking as well as for holes of all sorts. There are several facts related to its geometry and characteristics can be addressed.

Material to Be Machined

As tungsten carbide tools maintain a sharp cutting edge better than others, the tungsten carbide burs could be dealt with  most hard materials: metals including steel, aluminum and cast iron, stone, ceramic, porcelain, hard wood, acrylics, fibreglass and reinforced plastics.

Single Cut and Double Cut


Tungsten carbide burs usually comprises single cut and double cut. Since single cut tungsten carbide burr has a up cut spiral flute, which could get rid of material quickly with a smooth finish, it is an ideal solution for steel, copper,cast iron and ferrous metals.


Tungsten Carbide Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten-carbide.com.cn
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email:   sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn

Tungsten carbide tipped annular cutter is a cutting tool, made from tungsten carbide material on its tip, with multiple cutting edges and hollow body. Besides it owns advantages of extreme hardness and durability, it is also identified benefits in time saving, energy saving ,more finishing and etc..



Time Saving
Compared to conventional drill bits, the tungsten carbide tipped annular cutters are supposed to be 3 to 4 times faster, and instead of removing the complete material of the hole, the tungsten carbide annular cutter only has to eliminate less material, due to its cuts simply on the periphery of the hole. Furthermore, differently from conventional drill bits, annular cutters are one-shot operation,which do not need pre-drilling. The less teeth design also offers annular cutters’ hole making in higher speed and faster feed rate.


Tungsten Carbide Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten-carbide.com.cn
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email:   sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn

Energy Saving

Differently from the conventional drill bits, which has to cut through complete work pieces, the tungsten carbide annular cutter only removes the material on the periphery of hole. Since it requires less drive, the relevant energy requirement is less.

More Finishing

It proves that, by adopting tungsten carbide annular cutter in hole making, the result benefit in more finished , precise and accurate.

Efficient Cooling

The tungsten carbide annular cutter is internal cooling. With the help of a pilot pin, its internal lubrication is offered via the hollow body, which ensures more efficient and faster operation during the deep hole drilling.

Easy

Since the annular cutters have distinctive geometry, it could ease the awkward angles’ hole making.


Tungsten Carbide Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten-carbide.com.cn
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email:   sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn

Many studies have shown that tungsten powder largely depends on the final size of the tungsten oxide and reducing conditions. During the reduction process tungsten trioxide (WO3) major phase component has a great influence on the grain size of tungsten powder, to understand the  main phase ingredients of restore process in favor of to choose different raw materials and processing technology to produce different size tungsten powder (WP). After studies found that when the temperature at 500 ~ 600 ℃, the tungsten trioxide reaction occurs as WO3 → β- tungsten oxide → β-W → WP. And there are a small amount of β- tungsten oxide turn into tungsten dioxide (WO2), and then reduced to WP. When the reaction temperature is 600 ~ 800 ℃, the reaction as follow WO3 → β-tungsten oxide → dioxide, →tungsten dioxide → WP. In which a small amount of β- tungsten oxide restore to β-W and then into WP. When the temperature is 770 ~ 900 ℃, the reaction occurs as WO3 →β-tungsten oxide→ γ- tungsten oxide→tungsten dioxide→ WP. Besides after the morphological study found that tungsten trioxide is good for produce coarse particles tungsten powder, γ- tungsten oxide is suitable to obtain fine tungsten powder, β- tungsten oxide is somewhere in between.

Tungsten Manufacturer & Supplier: Chinatungsten Online - http://www.chinatungsten.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn
 

In the study the mechanism of gasochromic, using XRD diffraction and Raman spectroscopy to study the crystal structure changes and W-O bond vibrate mode changes which are tungsten trioxide nano wire film before and after coloring. The study showed, hydrogen ions and electrons in the double injection mode will cause a new tetragonal phase which is WO3-x • H2O. And it also leads to a significant change in the vibration pattern W-O bond. Through these study results put forward a gasochromic mechanistic models which is the structural water molecules and oxygen vacancies coexist in the nano wire body.

In WO6 hexahedral of WO3, the injection H + adsorbed in the vicinity of O2-, injection e- filled the bottom of the conduction band localized states WO3, resulting W6 + became W5 +. In hexahedral structure 6 oxygen are likely to absorb the H +, once one O adsorption of H +, the role of the W-O bond will become weak and O more active. It will easily re-adsorption 1 H + to form a structure of water molecules (H2O). When W-O bond weakening the structure is reconstruction, which the W remove to O direction, resulting in W-O bond lengths elongate and shorten the length of the other side of the WO bond. Then W-O bone effects can enhance, not easy to re-adsorbed H +. In the heat or light condition, the water structural molecules easy to fall off O, resulting in an oxygen vacancy. In this mode, involving the WO bond length flexible change better explain the coloring process of Raman spectrum.

Tungsten Manufacturer & Supplier: Chinatungsten Online - http://www.chinatungsten.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn
 

The researchers found that on the basis of double injection model, injection electrons being caught to form colored center is the main reason to cause material color change. But the studied found that injection of hydrogen will change material color. So the researchers have established a model structure of water molecules. Using thermogravimetric mass spectrometry technology can sure there are water structural molecules in WO3 nano wire film. Tungsten trioxide gasochromic water structural molecule can well explain the process of coloring.

In WO3 nano line film structures water molecule model, the coloring process Gasochromic can be described as, adsorbed H2 molecule which is on the Pt nano particles surface is ionized to become H atom, H atom transfer to the WO3 nano wire surface through spillover mechanism. Hydrogen ions and electrons injected into the WO3 lattice then hydrogen ions combine with O which is in the crystal lattice to water molecules. The structure water molecules will easy fall into its original position by thermal disturbance or light resulting oxygen vacancies. And at room temperature conditions it still remains inside of lattice, and will not discharge nano wire body. On the other hand, the injection electrons fill in bottom of conduction band localized state which is cause by oxygen vacancies in order to cause a change in W valence. (From W5 + becomes W6 +).

Tungsten Manufacturer & Supplier: Chinatungsten Online - http://www.chinatungsten.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn
 

After studies found the water structural molecules can well explain the gasochromic coloring process, the same it can also explain the bleaching process of gasochromic. gasochromic coloring and bleaching process is an exothermic combustion process, WO3 and Pt particles as catalysts. The bleaching process is as follows: When the colored nano wires under the conditions of air or oxygen, the O2 molecules adsorbed on the surface will cause ionization and transfer on the Pt nano particles surface. The O atoms which transfer to the tungsten trioxide will react with H to form hydroxyl which is on the surface of tungsten oxide. Then with the O atoms continuous transfer, O atoms in the nano wire surface by capturing free electrons form O2-. With the decrease of nano wire carrier concentration the donor level which is near local area oxygen vacancies become unstable. When the donor levels electron caught by oxygen atoms and localized on the surface of the nano wires the W ions valence state which is linked with oxygen vacancies atomic valence will fromW5 + back into the W6 +, causing localized structural water molecules instability. Finally, the structural water molecules dissolve into H + and O particles. On the one hand, H + diffusion to the nano wires surface then react with O which is adsorbed on the surface to form H2O molecules adsorbed into the air. On the other hand, O ions fill the oxygen vacancies, and the material structure return to the pre-colored WO3 structure, complete bleeding process of tungsten trioxide nanowire films.

Tungsten Manufacturer & Supplier: Chinatungsten Online - http://www.chinatungsten.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn
 

Tungsten oxide has many production methods, such as solid state method, liquid phase method which has widely used and chemical deposition method, sol-gel method, microemulsion method, hydrothermal synthesis method. And using different methods can produce different structure tungsten oxide ions, such as cubic crystal system, tetragonal crystal system, hexagonal crystal system, triclinic crystal system, orthorhombic crystal system and so on. With further researches a series of nonstoichiometric and metastable valence tungsten oxide compound come after another, the researchers called such oxide tungsten as bronze phase tungsten oxide and pyrochlore phase tungsten oxide. These special form tungsten oxide has larger changes occurred in t physical chemical properties. For example bronze tungsten oxide is a compound of a class of multi-dimensional pore structure, because it has a molecular sieve mesh structure and dielectric stability, significant changes in the physical and chemical properties of tungsten oxide bronze. Which are not only conductivity and adsorption properties strong in catalysis, sensing, electrochromic, fuel cells and other fields has been widely used. This also caused widespread concern, so that researchers continue to research and development tungsten oxide special form.

Tungsten Manufacturer & Supplier: Chinatungsten Online - http://www.chinatungsten.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn