Tungsten Carbide Fact
"Tungsten" (from the Swedish and Danish tung sten, means "hard-" or, more accurately, "heavy-stone") is used in English, French, Italian as the name of the element, although in many other languages (e.g. in German and Spanish) it is known as "wolfram", and this is also the origin of its chemical symbol, W and the atomic number is 74. Tungsten carbide, WC, or tungsten semicarbide, W2C, is a chemical compound containing tungsten and carbon. Colloquially, tungsten carbide is often simply called carbide. Our Tungsten Carbide Rings are composed of 85-88% of Tungsten Carbide, with a minority composition of materials including Tantalum, Titanium, Niobium and Chromium.

In its raw form, tungsten is a steel-gray metal that is often hard to work. Of all metals in pure form, tungsten has the highest melting point (3,422’C, 6,192 ’F), lowest vapor pressure and (at temperatures above 1,650’C) the highest tensile strength. Tungsten has the lowest coefficient of thermal expansion of any pure metal. It is remarkable for its robust physical properties, especially the fact that it has the highest melting point of all the non-alloyed metals and the second highest of all the elements after carbon.

Tungsten Carbide is the only metal that can be permanently polished and scratch-free. The polish and finish will virtually last forever and will never deform. It is 10 times harder than 18k gold, 5 times than steel and 4 times than titanium. Many people also enjoy the heavy weight of a tungsten carbide ring. The enduring polish of a tungsten ring together with the solid weight, speak of commitment, security and an everlasting bond.

High-tech Ceramic Fact
High-tech ceramic is commonly used in producing watch cases. The material is valued by watchmakers for its light weight, scratch-resistance, durability and smooth touch. IWC is one of the brands that initiated the use of ceramic in watch-making.

High-tech ceramic rings are the latest contemporary fashion trends. The term covers inorganic non-metallic materials which are formed by the action of heat. Basically, when heat is applied to ceramic, it forms an oxidized coating. This coating creates enables the ring to be 100% scratch resistant. The coating has the same strength of sapphire and will prevent much of the wear and tear. High-tech ceramic material is heavier than titanium, but lighter than tungsten carbide. It shares hypoallergenic qualities like black zirconium rings and titanium rings but offers a stylish look. Just like Tungsten Carbide, High-tech ceramic rings are permanently polished, scratch-free with everlasting durability.

Engraving and Customizations are Possible
Although both Tungsten Carbide and High-tech ceramic Rings are strong and hard to work with, we can still provide engraving service onto the rings and customizations on width and thickness are possible too.

Tungsten Carbide Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten-carbide.com.cn
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Overall Industry Structure:  The tungsten industry may be considered to comprise three principal divisions:

    Primary Tungsten Producers – the mines which mine and carry out primary mineral processing to produce tungsten mineral concentrates

    Secondary Tungsten Processors – the processing plants which take the mineral concentrates and process them into a number of tungsten powders, including ammonium paratungstate (APT), suitable for use in downstream metal/alloy manufacturing.  These powders are often referred to as “intermediates”

    Tertiary Tungsten Product Manufacturers – the plants which produce finished tungsten metal, tungsten alloys, tungsten tools and other tungsten end products.

Traditionally there has been some degree of vertical integration within the industry, with some common ownership of secondary processing and tertiary manufacturing facilities, but this integration rarely extended upstream to the primary producers, the miners. However, the expansion of the Chinese economy and the demand for tungsten has, apparently, resulted in considerable vertical integration in the tungsten industry in China, whether through common ownership or contractual arrangements, with a move away from exports of concentrates and into downstream processing and manufacturing. This pressure towards vertical integration within China and an apparent desire to secure long term concentrate supply, has resulted in various large Chinese companies investing in Western tungsten projects. This activity in China has started to affect the industry outside China, with a number of strategic mergers, acquisitions and investment within the Western tungsten industry over the last two years.

Tungsten Products:  The usages of tungsten result in an industry structured to produce various categories of products:

    Approximately 50% of tungsten is used in the production of hardmetals, or cemented carbides; these are cutting, drilling and wear materials formed from tungsten carbides and cobalt, and occasionally other minor metals such as titanium, tantalum and niobium

    Some 17% of tungsten is used to produce specialist steel alloys, such as high speed steel, heat resistant steel and tool steels, all largely utilised in metal cutting applications and specialist engineering applications

    In the region of 15% of tungsten would be used to make “mill products”; the mill products would comprise tungsten rod, sheet and wire, electrical contacts, etc…

    The balancing 18% of tungsten is used by the chemical industry and in other specialist applications.

World Tungsten Metal Production:  The total yearly tonnage of mine tungsten metal production is very small relative to base metals, the more recent estimates being:

    83,000t  of primary tungsten metal (W) production – equivalent to 105,000t of tungsten trioxide, WO3 (79.3% W)

The breakdown of this production would be circa:

    70,000t/ year W from Chinese mines  -  of the order of 84% of World production

    7,000t /year W from Western orientated economies  -  circa 9%

    6,000t/year W from other communist or CIS countries  -  circa 7%

Tungsten Pricing:  Prices for tungsten concentrates produced by mines and the intermediate tungsten powers produced by the secondary processors are quoted in metric tonne units (mtu). An mtu consists of 10kg of WO3, as contained within the particular material in question, concentrates or APT (this relationship conveniently results in the fact that a 1% resource grade equates to 1 mtu). The two materials for which prices are quoted widely and reported in mtu of WO3 are:

    tungsten trioxide, WO3, (containing 79.3% tungsten metal), as the critical constituent in the minerals in mine concentrates

    ammonium paratungstate, APT, the main secondary downstream product made from concentrates.

Tungsten Manufacturer & Supplier: Chinatungsten Online - http://www.chinatungsten.com
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This deals with the extraction of tungsten from tungsten(VI) oxide, WO3, produced from tungsten ores such as wolframite or scheelite.

Introduction

The production of the tungsten(VI) oxide from the ores is complicated, and not needed for any UK A level (or equivalent) syllabus. All we are interested in is the final reduction of the oxide to the metal.

Pure tungsten can't be obtained by reducing tungsten(VI) oxide using carbon, because it reacts with carbon to make tungsten carbide. Instead, the reducing agent is hydrogen.

The extraction process

Powdered tungsten(VI) oxide is heated to temperatures in the range 550 - 850°C in a stream of hydrogen.

An excess of hydrogen is used, and this carries away the steam produced during the reaction. The hydrogen is dried and recycled.

Great care obviously has to be taken to keep the whole system free of air to avoid explosion risks with the hydrogen at these high temperatures.

Tungsten Manufacturer & Supplier: Chinatungsten Online - http://www.chinatungsten.com
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Tungsten Metal (W):  From a mining and metal industry perspective, tungsten falls into a loose grouping of around 20 metals termed the minor metals (the other metal groupings being; the precious metals, the base metals and the platinum group metals (PGMs)).  Tungsten is unique in having a combination of relatively extreme properties compared to other metals; its properties include:

    a very high melting point, 3422°C (5700°C, boiling)  -  highest melting point of all metals

    a very dense, heavy metal, 19.25 g/cm2

    an extremely strong, wear resistant metal; has a hardness close to that of diamonds - highest modulus of elasticity and highest tensile strength of all metals

    a thermally and chemically stable metal, with high thermal conductivity - lowest coefficient of expansion of the metals

    a high electrical conductivity

    a relatively inert metal which does not oxidise readily, is extremely corrosive resistant and relatively acid resistant and is deemed environmentally benign.

Tungsten Uses:  As a consequence of tungsten metal’s properties, tungsten alloys are used in various application areas:

    Tungsten, due to its hardness and ability to withstand heat, is very suitable as a critical component of cutting tools used to drill or cut other metals, concrete or rock (e.g. household drill bits, metal fabrication tools, dentists tools, etc..)

    These attributes also make tungsten alloys suitable for critical temperature sensitive and wear resistant machinery components (e.g. engine valves, ball-point pen tips, turbine blades, snow tyre studs)

    These wear and temperature resistant properties, in combination with tungsten’s electrical conductivity, also make tungsten ideal as a critical temperature resistant component in electronics and as a contact point in electrical circuits (e.g. LCD panels, TV tubes, laser printers, window heating wires, car horns, electrical switch gear)

    Tungsten’s high density properties also make it suitable as a weight or counterbalance in specific machinery applications (airplane flaps, mobile phone vibration systems, crankcase balancing weights, golf clubs and as an environmentally acceptable substitute for lead shot in cartridges).

Tungsten Metals Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten.com.cn
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