Sapphire Grow Method - Micro-Pulling And Shoulder Expanding at Cooled Center (SAPMAC)

Micro-pulling and shoulder expanding at cooled center is a sapphire growth method, which is also called micro-pulling rotation Kyropoulos. The is an improved method based on Kyropoulos Method and Pulling Method by Institute of Composite Structures from the Harbin Institute of Technology. It is used to grow large size crystal. Crystal growing system includes control system, vacuum system, heating body, cooling system and thermal protection systems. The following a picture, which is a schematic shoulder cold heart to put the system trace Czochralski method, SAPMAC grown single crystal, the outlook is usually pear-shaped, crystal diameter crucible can grow to more than the inner diameter of the small size of 10 ~ 30mm. The seed is processed into split shape, use seed clips at the bottom of the heat exchanger. Rotating and pulling the heat exchanger can be accomplished seed fixed, crystals, and the exchange interaction between the heat exchanger, crystal and melt.

Cold Heart put the shoulder when trace Czochralski growth of sapphire crystals, usually the entire crystal growth process can be divided into four control phases, namely seeding, put the shoulder, and other tracks, annealing and cooling phases. Seeding stage and put the shoulder is the use of adjusting heat exchanger cooling capacity, appropriate with a certain reduction in heating temperature (heating system can provide the crucible outer wall temperature) way to achieve the crystal and put the shoulder necking control. At this time the crystal growth rate and temperature gradient interface projecting large, which is conducive to the use of larger discharge shoulders, reducing the distance to put the shoulder to prevent flipping interface, while capable of dislocation within the seed crystal defects such as the original fast from Crystals spread to the crystal surface, effectively reducing defects within the crystal content. Large temperature gradient also can increase the interface crystal growth driving force, increase the stability of the interface. Until crystals grow to the desired diameter size (cold shoulder put heart trace Czochralski crystal diameter can grow from the inner wall of the crucible 1 ~ 3cm), crystals begin Equal grow into other tracks stage. With grown crystal size, heat exchanger efficiency of crystal growth decreases rapidly, so the crystal enters Once diameter growth stage, mainly by reducing the heating temperature(Crucible outer wall temperature of the heating system can provide) to achieve crystal growth.

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Sapphire Grow Method-Vertical Horizontal Gradient Freezing (VHGF)

Vertical horizontal Gradient freezing method is shorted to VHGF method, which is a method used for producing large quantity sapphire crystal. This technique is a vertical temperature gradient cooling system based on the law, and the use of VGF grown GaAs crystal rods, low potential density can reach high quality crystal rods. VGF is divided based on the law, the combination of the horizontal temperature gradient cooling process, this way, can long grain size (diameter and height) and long-grain shape is relatively unrestricted.



Chunks of polycrystalline, produced by horizontal synthesis, are placed in a crucible with a seed crystal of the required orientation. The crucible is then placed vertically in a furnace and a temperature gradient is moved up the length of the crystal (away from the seed).

Single crystal growth propagates from the seed crystal and, because the crystal forms in the shape of the crucible, diameter control of the ingot is relatively simple.

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Sapphire Growth Method- Vertical Gradient Freeze Method (VGF)

Vertical gradient freeze method is similar to the level of zone melting, mainly in the way of moving the crucible, so that a temperature gradient within the molten metal, and then began to grow crystals. This method used by the heater is divided into two parts, the top of the furnace body heater temperature is higher, lower temperature below the temperature difference generated by the heater caused the temperature gradients, thus growing crystals. Because of the growth process, the temperature of the heater is constant, and the heater from the solid-liquid interface of the crystal growth when it is fixed, in which case you must make Bridgman, make molten metal through the solid-liquid interface, the use of VGF way, it solidified molten metal normal form a single crystal. Its growth principle is as the picture showing.

The features of VGF method are as following:
1) The shape of the crystals may vary depending on the shape of a crucible for growing profiled crystals;
2) Plusing the seed crystal growth orientation can also be natural nucleation, based on the principles of geometry out of the crystal growth;
3) This method can be closed or semi-closed crucible to grow. Prevent evaporation melt dopant, resulting in compositional deviation and doping concentration, and can be on the surrounding environment pollution and hazardous substances;
4) It is suitable for large size, growing large number of crystals. A furnace can grow a few or dozens of different root, different sizes of crystals.
5) Operation process is relatively simple, easy to implement procedures and automation. VGF main drawbacks as follows:

Processes of VGF:
1) The whole process of crystal growth is carried out inside the crucible, which is not easy to observe the growth because of the invisible material of tungsten. If the crucible is not made of tungsten, mo, or other metals, but glass, then it would be different.
2) Different crystals require specify physical and chemical properties of the crucible. Especially in matching the crucible and the thermal expansion coefficient of crystalline material to the right, while unsuitable for crystal growth of crystalline material volume expansion.
3) Tungsten crucible will stress and create parasitic crystal nucleation crystal during the sapphire growth. Therefore, the requirement of inner surface finish for crucible is very high.
4) When using Vertical Gradient Freeze method to grow sapphire crystal, the going down of crucible is not rotating, so that the quality of crystal is not better than the one grows out by grow out by Czochralski method.

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Sapphire Growth Method- Temperature Gradient Technique (TGT)

Temperaturegradient technique, shorted to TGT, is one of sapphire growth methods, invented by Zhou Yongzong and the staff of Shanghai Institute of Optics and Fine Mechanics in China. This method applied orientation seed to grow sapphire. Physical process of TGT: 

Climatology
On a global and annual basis, the dynamics of the atmosphere (and the oceans) can be understood as attempting to reduce the large difference of temperature between the poles and the equator by redistributing warm and cold air and water, known as Earth's heat engine.

Meteorology
Differences in air temperature between different locations are critical in weather forecasting and climate. The absorption of solar light at or near the planetary surface increases the temperature gradient and may result in convection (a major process of cloud formation, often associated with precipitation). Meteorological fronts are regions where the horizontal temperature gradient may reach relatively high values, as these are boundaries between air masses with rather distinct properties.

Clearly, the temperature gradient may change substantially in time, as a result of diurnal or seasonal heating and cooling for instance. This most likely happens during an inversion. For instance, during the day the temperature at ground level may be cold while it's warmer up in the atmosphere. As the day shifts over to night the temperature might drop rapidly while at other places on the land stay warmer or cooler at the same elevation. This happens on the West Coast of the United States sometimes due to geography.

Weathering
Expansion and contraction of rock, caused by temperature changes during a wildfire, through thermal stress weathering, may result in thermal shock and subsequent structure failure.

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Tungsten Heat Shield Price on Dec. 19, 2017

Tungsten heatshield price is 370.00USD/PC on Dec. 19, 2017, EXW, Xiamen, China. This quotation is for sapphire growth furnace industry, which is not used separately. The quotation is for one piece, and we can produce and install the whole set if you can provide us your idea or drawings.

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Leybold Tungsten Filament Price on Dec.19, 2017

Leybold tungsten filament price is 8.00USD/PC on Sep. 30, 2017, EXW, Xiamen, China. This kind of filament is used in Leybold machine, with a diameter of 0.6mm and length of 30.2mm.

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Tungsten Granule Price on Dec. 23, 2017

Tungsten granule price is 67.20USD/KG on Sep. 30, 2017, EXW, Xiamen, China. Tungsten granule is mainly used for carbon and sulfur analysis and the most widely used grain size is 20~40mesh.

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Cerium Tungsten Electrode Price on Dec. 19, 2017

Cerium tungsten electrode price is 0.877USD/PC on Dec. 19, 2017, EXW, Xiamen, China. The content of CeO2 is 1.7~2.2%, its tip color is grey. The international standard of tungsten electrode is ISO6848.

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Sapphire Growth Method - Heat Exchanger Method (HEM)

Heat Exchanger Method (HEM) is one of sapphire growth method, which is used to grow the sapphire with large size. Since 1970s, Schmid and Viechnicki applied HEM to grow a big sapphire crystal, and the method is used popular and popular. 

Its basic principle is to apply a heat exchanger to dissipate heat, making the crystal growth region forming a longitudinal cold hot temperature gradient. By controlling the volume of gas flow inside heat exchanger and changing the heating powder, the gradient can be kept. Then the crystal can grow slowly from the bottom to the upper part. Following is a pic to show the structure and principle of the growing method.  

Tungsten crucible is used in the middle of furnace, and sapphire is growing in the crucible.      

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Sapphire Growth Method - Edge-defined Film-fed Growth (EFG)

The following picture is to show the growth principle of Edge-defined Film-Fed Growth Method. First put raw material into the fluid which carried by tungsten crucible. Heating by the heating coils, and melting the raw material, then using the mold to smooth the material on the surface of the mold by applied Capillary action, so that a thin film will formed. Follow on, the sapphire seed is brought into the fluid, and connected with the thin film. And the thin film will crystallized the same structure as sapphire seed. The seed will be pulling up slowing, and growing slowing. Tungsten crucible is one of the main part in the furnace.

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Sapphire Growth Method - Czochralski Method

The Czochralski Method is a method of crystal growth used to obtain single crystals of semiconductors (e.g. silicon, germanium and gallium arsenide), metals (e.g. palladium, platinum, silver, gold), salts and synthetic gemstones. The process is named after Polish scientist Jan Czochralski who invented the method in 1916 while investigating the crystallization rates of metals.

Tungsten crucible is the medium for growing sapphire in this method.

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Sapphire Growth Method - Kyropoulos Method

Kyropoulos method can be shorted as KY method. This method is the first to propose to grow crystals in 1926. Later on, it is widely used in the production and research of large-size crystal halogen, hydroxide and carbonate crystals. In 1960s and 1970s, it is improved by former Soviet Union Musatov for the production of sapphire crystals. The furnace is used tungsten crucible as growing crucible.

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Tungsten Heat Shield Price on Sep. 30, 2017

Tungsten heat shield price is 360.00USD/PC on Sep. 30, 2017, EXW, Xiamen, China. This quotation is for sapphire growth furnace industry, which is not used separately. The quotation is for one piece, and we can produce and install the whole set if you can provide us your idea or drawings.

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Coil Tungsten Filament Price on Sep.30, 2017

Coil tungsten filament price is 2.80USD/PC on Sep. 30, 2017, EXW, Xiamen, China. This type of electron beam tungsten filament cost is not mainly influenced by the raw material, so the price can be kept or increased not so greatly during the raw material rapid increasing period.

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Tungsten Granule Price on Sep. 30, 2017

Tungsten granule price is 67.20USD/KG on Sep. 30, 2017, EXW, Xiamen, China. Tungsten granule is mainly used for carbon and sulfur analysis and the most widely used grain size is 20~40mesh.

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Lanthanum Tungsten Electrode Price on Sep. 30, 2017

Lanthanumtungsten electrode price is 1.600USD/PC on Sep. 30, 2017, EXW, Xiamen, China. Tungsten electrodes keeps increasing in early Sep. and going to stable status in mid, then a bit decreasing in end Sep. meanwhile, as for the coming Chinese National Holiday and Mid-autumn Festival, the tungsten market is not so active than usual.

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Tungsten Filament in Electron Accelerator

An electron accelerator includes a vacuum chamber having an electron beam exit window. An electron generator is positioned within the vacuum chamber for generating electrons. A housing surrounds the electron generator and has a first series of openings formed in the housing between the electron generator and the exit window for allowing electrons to accelerate from the electron generator out the exit window in an electron beam when a voltage potential is applied between the housing and the exit window. The housing also has a second series and third series of openings formed in the housing on opposite sides of the electron generator for causing electrons to be uniformly distributed across the electron beam by flattening electrical field lines between the electron generator and the exit window. Tungsten filament is installed in electron equipment, to work with accelerator, film, exit window to emit the electron. 

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Electron Beam Tungsten Filament and Exit Window Foil

An exit window for an electron beam emitter through which electrons pass in an electron beam includes an exit window foil having an interior and an exterior surface with a series of holes formed therethrough. A corrosion resistant layer having high thermal conductivity extends over the exterior surface and the holes of the exit window foil for resisting corrosion and increasing thermal conductivity. The layer extending over the holes of the exit window foil provide thinner window regions which allow easier passage of the electrons through the exit window. And the emitting electrode is generated by tungsten filament with customized shapes. 

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Electron Beam Tungsten Filament Applications

Electron beam tungsten filament applications are coating thin film in making Christmas ball, bottle cap, shoe heel, reflection cap, lamp industry etc, as a heater in vacuum metalizing machine. Tungsten filament is with properties of high melting point, high resistance, good intensity and low evaporation pressure, suitable for making heating element. Placing film material (aluminum, chrome, indium etc.) in vacuum metalizing machine, with high vacuum, the heating element (tungsten heater) will evaporate the film turn into shiny and beautiful film.

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Electron Beam Tungsten Filament for Laybold

This is a type of tungsten filament, made by tungsten wire. This design is for Germany Laybold vacuum furnace.

Regular sizes are Ø0.55 and 0.8mm.

Regular packing is 10pcs in a paper box.

Shape: two legs with center coils

MOQ: 1pc (If we have produced in stock), mostly 10pcs would be better.

Delivery: by TNT, DHL, FEDEX, UPS, ETC.

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Electron Beam Tungsten Filament for Telemark

This is a type of tungsten filament, made by tungsten wire. This design is for USA Telemark.

Regular sizes are Ø0.55 and 0.8mm

Regular packing is 10pcs in a paper box

Shape: two legs with center coils

MOQ: 1pc (If we have produced in stock), mostly 10pcs would be better

Delivery: by TNT, DHL, FEDEX, UPS, ETC

More details, you can visit http://tungsten.com.cn/EB-tungsten-filament.html.

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Tungsten Cathode for Electron Beam Emitter

Design and development of an indirectly heated solid cathode for a linear electron beam emitter assembly can be found as following image. The solid cathode is made of tungsten with cathode shape, called tungsten cathode. Thermionic electron beams emitted from a directly heated strip shaped filament have been used to heat the cathode indirectly. The temperature of the cathode, measured by a two color pyrometer, was raised to 250002K. The innovative design of the cathode and its holding mechanism accommodates thermal expansion at high temperature, and prevents thermal deformation of the cathode. The cathode is suitable for use in strip electron beam gun and for laboratory experiments on melting and evaporation of refractory materials.

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Electron Beam Emitter

An electron beam emitter including a vacuum chamber having a width. An electron generator can be positioned within the vacuum chamber for generating electrons. An elongate nozzle can extend from the vacuum chamber along a longitudinal axis and have an exit window at a distal end of the nozzle. The nozzle can have a width that is less than the width of the vacuum chamber. The electron generator can be shaped and dimensioned, and positioned with the vacuum chamber to form and direct a narrow electron beam that enters and travels through the nozzle, and exits out the exit window. Used for irradiation of bottle interior. Tungsten filament is a main part for emitting electron.

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Electron Beam Tungsten Filament for JEBG-203

This is a type of tungsten filament, made by tungsten wire. This design is for Japan JEBG-203. 

Regular sizes are Ø0.55 and 0.8mm.

Regular packing is 10pcs in a paper box.

Shape: mosquito coil

MOQ: 1pc (If we have produced in stock), mostly 10pcs would be better.

Delivery: by TNT, DHL, FEDEX, UPS, ETC.

More details, you can visit http://tungsten.com.cn/EB-tungsten-filament.html.

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Thorium Tungsten Electrode Price on Jul. 27, 2017

Ø3.2x150mmthorium tungsten electrode price is USD1.326/PC on Jul. 27, 2017. WT20 is the most popular grade for thorium tungsten electrode, and it has been the most expensive electrode compared to other kinds, such as pure tungsten electrode, etc.

GTAW Safety

Welders wear protective clothing, including light and thin leather gloves and protective long sleeve shirts with high collars, to avoid exposure to strong ultraviolet light. Due to the absence of smoke in GTAW, the electric arc light is not covered by fumes and particulate matter as in stick welding or shielded metal arc welding, and thus is a great deal brighter, subjecting operators to strong ultraviolet light. The welding arc has a different range and strength of UV light wavelengths from sunlight, but the welder is very close to the source and the light intensity is very strong. Potential arc light damage includes accidental flashes to the eye or arc eye and skin damage similar to strong sunburn. Operators wear opaque helmets with dark eye lenses and full head and neck coverage to prevent this exposure to UV light. Modern helmets often feature a liquid crystal-type face plate that self-darkens upon exposure to the bright light of the struck arc. Transparent welding curtains, made of a polyvinyl chloride plastic film, are often used to shield nearby workers and bystanders from exposure to the UV light from the electric arc.

Welders are also often exposed to dangerous gases and particulate matter. While the process doesn't produce smoke, the brightness of the arc in GTAW can break down surrounding air to form ozone and nitric oxides. The ozone and nitric oxides react with lung tissue and moisture to create nitric acid and ozone burn. Ozone and nitric oxide levels are moderate, but exposure duration, repeated exposure, and the quality and quantity of fume extraction, and air change in the room must be monitored. Welders who do not work safely can contract emphysema and oedema of the lungs, which can lead to early death. Similarly, the heat from the arc can cause poisonous fumes to form from cleaning and degreasing materials. Cleaning operations using these agents should not be performed near the site of welding, and proper ventilation is necessary to protect the welder.

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GTAW Technique

GTAW Welders often develop a technique of rapidly alternating between moving the torch forward (to advance the weld pool) and adding filler metal. The filler rod is withdrawn from the weld pool each time the electrode advances, but it is always kept inside the gas shield to prevent oxidation of its surface and contamination of the weld. Filler rods composed of metals with a low melting temperature, such as aluminum, require that the operator maintain some distance from the arc while staying inside the gas shield. If held too close to the arc, the filler rod can melt before it makes contact with the weld puddle. As the weld nears completion, the arc current is often gradually reduced to allow the weld crater to solidify and prevent the formation of crater cracks at the end of the weld.

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GTAW Manual

Manual gas tungsten arc welding is a relatively difficult welding method, due to the coordination required by the welder. Similar to torch welding, GTAW normally requires two hands, since most applications require that the welder manually feed a filler metal into the weld area with one hand while manipulating the welding torch in the other. Maintaining a short arc length, while preventing contact between the electrode and the workpiece, is also important.

To strike the welding arc, a high frequency generator (similar to a Tesla coil) provides an electric spark. This spark is a conductive path for the welding current through the shielding gas and allows the arc to be initiated while the electrode and the workpiece are separated, typically about 1.5–3 mm (0.06–0.12 in) apart.

Once the arc is struck, the welder moves the torch in a small circle to create a welding pool, the size of which depends on the size of the electrode and the amount of current. While maintaining a constant separation between the tungsten electrode and the workpiece, the operator then moves the torch back slightly and tilts it backward about 10–15 degrees from vertical. Filler metal is added manually to the front end of the weld pool as it is needed.

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History of GTAW - Plasma Arc Welding

Developments continued during the following decades. Linde developed water-cooled torches that helped prevent overheating when welding with high currents. During the 1950s, as the process continued to gain popularity, some users turned to carbon dioxide as an alternative to the more expensive welding atmospheres consisting of argon and helium, but this proved unacceptable for welding aluminum and magnesium because it reduced weld quality, so it is rarely used with GTAW today. The use of any shielding gas containing an oxygen compound, such as carbon dioxide, quickly contaminates the tungsten electrode, making it unsuitable for the TIG process. In 1953, a new process based on GTAW was developed, called plasma arc welding. It affords greater control and improves weld quality by using a nozzle to focus the electric arc, but is largely limited to automated systems, whereas GTAW remains primarily a manual, hand-held method. Development within the GTAW process has continued as well, and today a number of variations exist. Among the most popular are the pulsed-current, manual programmed, hot-wire, dabber, and increased penetration GTAW methods.

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History of GTAW - Heliarc

Russell Meredith of Northrop Aircraft perfected the process in 1941. Meredith named the process Heliarc because it used a tungsten electrode arc and helium as a shielding gas, but it is often referred to as tungsten inert gas welding (TIG). The American Welding Society's official term is gas tungsten arc welding (GTAW). Linde Air Products developed a wide range of air-cooled and water-cooled torches, gas lenses to improve shielding, and other accessories that increased the use of the process. Initially, the electrode overheated quickly and, despite tungsten's high melting temperature, particles of tungsten were transferred to the weld. To address this problem, the polarity of the electrode was changed from positive to negative, but the change made it unsuitable for welding many non-ferrous materials. Finally, the development of alternating current units made it possible to stabilize the arc and produce high quality aluminum and magnesium welds.

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History of GTAW - Gas-shielded Welding

The history of GTAW can be traced up to 19 century, which is by improving the welding and tungsten electrode is not the first material to be found for welding. After the discovery of the short pulsed electric arc in 1800 by Humphry Davy and of the continuous electric arc in 1802 by Vasily Petrov, arc welding developed slowly. C. L. Coffin had the idea of welding in an inert gas atmosphere in 1890, but even in the early 20th century, welding non-ferrous materials such as aluminum and magnesium remained difficult because these metals react rapidly with the air and result in porous, dross-filled welds Processes using flux-covered electrodes did not satisfactorily protect the weld area from contamination. To solve the problem, bottled inert gases were used in the beginning of the 1930s. A few years later, a direct current, gas-shielded welding process emerged in the aircraft industry for welding magnesium.

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GTAW Application

GTAW is most commonly used to weld thin sections of stainless steel and non-ferrous metals such as aluminum, magnesium, and copper alloys by using tungstenelectrodes. The process grants the operator greater control over the weld than competing processes such as shielded metal arc welding and gas metal arc welding, allowing for stronger, higher quality welds. However, GTAW is comparatively more complex and difficult to master, and furthermore, it is significantly slower than most other welding techniques. A related process, plasma arc welding, uses a slightly different welding torch to create a more focused welding arc and as a result is often automated.

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TIG and GTAW

Gas tungsten arc welding (GTAW), also known as tungsten inert gas (TIG) welding, is an arc welding process that uses a non-consumable tungsten electrode to produce the weld. The weld area and electrode is protected from oxidation or other atmospheric contamination by an inert shielding gas (argon or helium), and a filler metal is normally used, though some welds, known as autogenous welds, do not require it. A constant-current welding power supply produces electrical energy, which is conducted across the arc through a column of highly ionized gas and metal vapors known as a plasma.

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Tungsten Electrode TIG Welding

Tungsten Electrode TIG Welding introduces inert gas argon arc tungsten welding, including tungsten welding, welding equipment, gas protection, filling material, welding groove, welding operation technology, welding technique, welding metals, tungsten welding practice, welding cost and consumption.

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Tungsten Book - China Tungsten Industry

China Tungsten Industry is a book name to introduce tungsten industry.

China Tungsten Industry introduces recovery, development, history, properties, application, reserve, prospecting theory and technology, mining technology and equipment, mineral separation, smelting technology and equipment, processing technology and equipment, comprehensive utilization of resources and technology of circular economy, China and international production capacity, import and export trade and consumption, as well as the relevant laws, regulations and industrial policies.

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Tungsten Book - Tungsten Molybdenum Metallurgy

Tungsten Molybdenum Metallurgy is a book to introduce tungsten.

This is a book belongs to Rare Earth Metallurgy and Material Engineering Series Books with whole 12 chapters. Systematically set forth the theoretical basis and production practice of tungsten and molybdenum metallurgy, including tungsten, molybdenum and their compounds properties, resources, refining, tungsten carbide, tungsten molybdenum alloy, recycling, tungsten molybdenum economy, production technology, etc.

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Tungsten Standards

The tungsten standards include Chinese national standards, industrial standards and international standards.
GBT 3875 2006 Tungsten Plate
This Chinese national standard applied for tungsten plate produced by powder metallurgy.

GBT 3500 2008 Powder Metallurgy Terms
This standard introduces terms of powder metallurgy.

GBT 3457 1998 Tungsten Oxide
This standard specifies oxide kind, technology requirement, and inspection rules. The attachment is blue tungsten oxide testing method.

GBT 2967 2008 Cast Tungsten Carbide Powder
This standard is applicable to cast tungsten carbide powder used for surface reinforcement of oil drilling tools, building materials machinery, sugar cane crushing tools, grain machinery and other wear parts.

GBT 1479.1 2011 Powder Scott Density Testing
This standard shows powder Scott density testing.

GB 11247.2 1989 Tungsten Heater
This standard applied for vacuum coating tungsten heater.

GB/T 4295-2008 Tungsten Carbide Powder
This standard provides tungsten carbide powder requirement, testing method, inspection method, marks, packing, transport and storage.

GB/T 10116-2007 Ammonium Paratungstate
This standard provides ammonium paratungstate requirement, testing method, inspection method, marks, packing, transport and storage.

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Tungsten Vocabulary

Tungsten vocabulary gathers words of tungsten raw material, tungsten products, or words used during production.

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Tungsten HS Code

Tungsten HS code is harmonization system code, used to differ substances, such as tungsten, tungsten metal, tungsten powder, tungsten scrap, tungsten wire and others internationally.

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Tungsten Density

Density is analyzed as volumetric mass density to describe the weight/mass per unit volume of a substance. Tungsten density is the density of tungsten metals, such as pure tungsten metal density is 19.2g/cm3. It is shorted as ρ.

Ρ=m/v. this is a method to calculate the density of solid, powder or fluid. M is mass, is the weight of substance. V is volume for substance.

For solid metal, m can be weighted by scales. V can be calculated by Archimedes principle. But this method is not suitable for density testing of tungsten in powder shape. When to calculate density of tungsten powder, a bottle 1L is used. Let powder free fall down through a mesh, into the bottle, after the bottle is full, weight the bottle, minus bottle weight, then the final weight value is density of the powder.

As for tungsten is with high density, tungsten alloy and tungsten carbide products density will be lower when the content of tungsten is lower.


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Tungsten CAS Number

Tungsten CAS number is also written as tungsten CAS No. and tungsten CAS #, is a kind of number of describing different kind of materials.

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