DEEP HOLE DRILLING INSERTS,LATHE MACHINE CUTTING TOOLS,CARBIDE INSERTS

Fluorine-18 tungsten radiation shielding is usually used to shield radiation released when producing and using fluorine-18 and its compounds.Fluorine-18 is a radioisotope of fluorine with half-life of 109.771 minutes that plays an important role in positron source. It decays by positron emission 97% of the time and electron capture 3% of the time. Both forms of decay yield stable oxygen-18. Fluorine-18 is primarily synthesized into fluorodeoxyglucose to use in the radiopharmaceutical industry. It can be used as a tracer in positron emission tomography scan. Use of this tracer to detect the possibility of cancer metastasis is the most frequent type of PET scan in standard medical care.

Fluorodeoxyglucose also can be applied to evaluate the glucose metabolism in the heart, lungs and the brain, and to image tumors in oncology, where a static F-FDG PET scan is performed and the tumor F-FDG uptake is analyzed according to Standardized Uptake Value. FDG-PET can be used for diagnosis, staging, Surface Milling Inserts and monitoring treatment of cancers, particularly in Hodgkin's disease, non-Hodgkin's lymphoma, breast cancer, melanoma, colorectal cancer, and lung cancer. It has also been approved for using in diagnosing Alzheimer's disease. Since fluorine-18 is radioactive and toxic, tungsten radiation shielding is usually used to shield radiation released when producing and using fluorine-18 and its compounds.

Fluorine-18 tungsten radiation shielding is made of tungsten alloy with high density. According to the research, the radiation shielding performance of a metal material is closely related to its density .AS the density is higher, the radiation shielding performance is greater. Therefore the radiation shielding performance of fluorine-18 tungsten radiation shielding is great. Fluorine-18 tungsten radiation shielding is a best choice for shielding radiation generated during the preparation and the use of fluorine-18 and its compounds. In addition, tungsten alloy is environmental non-toxic so as not to pollute the environment or endanger human health.

Traditional mechanical process refers to the treatment of the surface, such as grinding, sand blast and so on. When it used in the CVD diamond coated carbide tools, which is the main means of mechanical polishing and ultrasonic cleaning. Mainly using diamond abrasive powder or fine diamond paste on respective base body is polished such that the surface of the substrate or the surface of the large number of mechanical scratches or shallow grooves, resulting in surface defect density is increased and the expansion of diamond nucleation sites. Solid surface defect position contains a large amount of lattice edges and kinks order, with crystal particles have higher binding force, thereby reducing the diamond nucleation free energy and enhanced nucleation effect. In addition, remain on the substrate surface diamond fine powder can be used as a seed diamond nucleation, which is one of main reason that the use of this method can greatly improve the adhesion of diamond nucleation density and the surface of the substrate.

Foreign researchers related use diamond grinding wheel for tungsten carbide matrix grinding, deposits a layer of diamond film in the process of applying the transition layer the above mentioned, through the gap between detection experiments prove diamond film and the cemented carbide substrate having good adhesion. However, after the grinding process, the surface of cemented carbide leaves more scratches, shallow pit, which will make the diamond nucleation density increase by a certain degree of influence. Meanwhile, it not only causes the damage of the surface of tungsten carbide matrix, but also has worse reuse, especially for the electronics and optics products with high demand of precision has a bad influence.

drilling inserts suppliers

Tungsten copper is a kind of psudoalloy, which is composed of W with body-centered cubic structure (bcc) and Cu with face-centered cubic (fcc) structure and they are immiscible or not forming intermetallic compound. It not only has high hardness, high strength, low coefficient of thermal expansion and excellent wear resistance and corrosion resistance of W, but also has excellent electrical conductivity, thermal conductivity and plasticity, which can be widely used carbide Drilling Inserts in some electrical contact materials or electrode materials. Generally, the basic process is: mixing → forming → infiltration, sintering → post-processing.

But tungsten copper electrode fabricated by conventional process, regardless of liquid-phase sintering or solid-phase sintering, the relative density of tungsten copper products produced will lower than 98% because of the wetting angle and the insoluble W in liquid Cu. Although the heating process and re-pressing or re-sintering can remarkably improve this situation, the cost is increasing and the overall efficiency is decreasing. Furthermore, in the sintering process will happen inevitably growth of tungsten grains, which would make it difficult to meet the performance of the market demands tungsten copper electrode material now.

In order to improve the sintering density of tungsten copper electrode and other tungsten copper composite materials, relevant researchers use activated sintering by adding additives. However, the activator can significantly improve the density of tungsten-copper alloy, it will also have some effects on the electrical and thermal conductivity, which is not suitable for the occasions has high demands on electrical and thermal conductivity. So chemical co-precipitation of copper tungsten nano composite powder prepared by reduction combined with hydrogen, by pressing and sintering process to obtain a high-performance compact tungsten copper alloy electrodes become a new hotspot.

The mechanical watche is one of the watches with high practical and decorative, which works by the winder of mechanical watch movement to spur the gearwheel to promote the watch dial pointer to walk . It seems that the mechanical watches are very complex with a lot of small parts, but its main working theory is that using the power produced by the winder to drive the pointer mounted on the power transmission gearwheel walking. The balance wheel and gearwheel are two important parts which composed the mechanical watches movements. To achieve the accuracy of the adjustment  clocks’ travel time, the most commonly used way is to adjust the balance wheel, that is to adjust the balance wheel running inertial and balance by the balance wheel own physical milling inserts attributes, provided screws counterweights or the eccentric weights, etc. The common balance wheel can be seen as follows: bimetallic compensation screw balance wheel, ring balance wheel, balance screw balance wheel, weight balance wheel, balance wheel in tune and so on.

Currently, methods to synthesize tungsten bronze compounds mainly are the wet chemical method, heat reduction method and thermal decomposition method. Wet chemical method to synthesize ammonium tungsten bronze is to put the starting material in the reducing solvent refluxing for several days, size of the sample obtained by this method is too large, it’s usually between a few to ten micron, and the preparation process Common Turning Inserts requires a long time and high energy consumption. Thermal reduction method is to uniformly mix tungsten oxide, tungsten powder and metal tungstates in proper proportions, then heated in a vacuum or under an inert atmosphere, the reaction temperature is usually about 1000 ℃, and remove unreacted impurities after the reaction is completed. Since the thermal stability of ammonium tungsten bronze difference is poor and decomposition temperature (300 ℃) is lower than the synthesis temperature, the thermal reduction method can not be used to synthesize ammonium tungsten bronze. The thermal decomposition method to synthesize ammonium tungsten bronze is to heat and decompose ammonium paratungstate in a reducing atmosphere (H₂ or a mixed gas of H₂, Ar, etc.), the size of the resulting sample is too large, and this method can not obtain completely pure phase ammonium tungsten bronze, ammonium content in sample is too low and easy to excessive decomposed into tungsten oxide.