The name "tungsten" is derived from the Swedish term meaning "heavy stone".  Tungsten has been assigned the chemical symbol W after its German name wolfram.  While sometimes regarded as a scarce or exotic metal, its abundance in nature is actually about the same as that of copper.  The largest known tungsten reserves are in mainland China, though plentiful reserves also exist in North America.

Tungsten has the highest melting point (3410°C or 6170°F) of all metals.  The extremely high melting point of pure tungsten makes all the common manufacturing techniques used for metals such as iron impractical.  Specialized methods make possible the processing of pure tungsten into rod, sheet, and wire for a wide variety of high temperature applications including incandescent lamp wire, TIG welding electrodes, and high temperature heat shielding.

Another important industrial property of tungsten is its high density of 19.3 g/cc (0.70 lbs/in³).  In addition to high gravimetric density, its high radiographic density makes it an ideal material for shielding or collimating energetic x- and g-radiation.  For such applications, tungsten is commonly alloyed in order to circumvent the extremely high processing temperatures that would otherwise be required to melt and cast the pure metal. 


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On May 29^th 2013, there was an article in South China Morning Post of Hong Kong named as 3D Printer Promotes the Development of Chinese aircraft. For aircraft enthusiasts, it is not a dream that use computer and 3D printer to manufacture a small plastic aircraft. How about manufacturing a real aircraft?

The Chinese scientists and aeronautical engineer consider that can be realized. They have began to use 3D printer to manufacturer refractory metal aircraft parts without molding, forging, assembling or other traditional manufacturing processes.

3D printing, also called as laser rapid prototyping is a newly developing manufacturing technique. 3D printers can transform blueprint on computer into material object directly by overlying materials layer by layer until finished products.

Refractory metal aircraft parts, being manufactured by 3D printing technique have been widely used for C-919 the first Chinese civil aircraft, J-15 the first carrier fight, J-16 multipurpose fighter-bomber, J-20 the first Chinese stealth fighter and J-31 the fifth generation fighter.

Traditional aviation industry not only spends too much time, and it also wastes a lot of materials. In generally, only 10 percent of raw materials are utilized. The rest are lost during the processes of molding, forging, cutting and burnishing. F-22 fighter which developed by Lockheed Martin in the U.S. needs 2796kg titanium alloy. In fact, only 144kg is utilized.

Sidney Wong, the associate dean of Enterprise Development Department in Hong Kong Polytechnic University showed that 3D printing technique could accelerate the development of Chinese new generation aircraft. He said, “3D printing technique can save time and materials. Researchers can print refractory metal aircraft parts directly in a short time. The cost of prototype is low without molding or any other complicated traditional processes and scientists can manufacture constantly more repetitions for test.”

Professor Wang Huaming, the expert of aerial material in Beijing University of Aeronautics & Astronautics considered that Chinese 3D printing technique had exceeded the U.S. because the U.S. could only manufacture small products by using the technique. However, Luo Jun, the CEO of Asian Manufacturing Association in Beijing considered that the Chinese printing technique still fell behind the West.


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In August of 1986 the last revision of the “Proposed Military Specification” for Tungsten Base Metal, High Density (MIL-T-21014D) was issued. In use for many years this specification defined the requirements for four classes of machinable, high density tungsten base metal produced by consolidating metal powder mixtures comprised primarily of tungsten. The alloy classes differed in tungsten content and density. The specification defined four slightly magnetic tungsten alloys (containing Ni-Fe binders) and three nonmagnetic tungsten alloys (containing Ni-Cu binders) in terms of their composition, mechanical properties, and machinability. ASTM approved a standard containing essentially the same content in 1987. The most recent revision of the ASTM standard (ASTM B777-07) was published in November of 2007 and is the active standard for tungsten alloys at this time. A third standard was introduced in August of 1998 by the Society of Automotive Engineers (SAE Technical Standard AMS-T-21014). All three of these standards contained the same set of mechanical properties for the various alloy classes. These properties are summarized in the table below.

There are various kinds of test for penetration of EFP (explosively formed penetrators). The first method is utilizing impulse X radiography to know the speed and attitude of EFP before or after penetrating, residues of EFP after penetrating and the fragments after penetrating target. Because strong flashing light and smoke accompany with the process of penetrating. For that, the only method to know the influence of EFP on target and the situation after penetrating target is adopting X-ray radiography. So impulse X-ray radiography has significance for research on penetrating mechanism of EFP. However X-ray may do harm to health during test. So the protection to researchers is necessary. Tungsten alloy shielding tube is made of tungsten alloy for protecting researchers from damaging of X-ray. Tungsten alloy shielding tube has good performance of radiation to radioactive substance for the high density of tungsten alloy. Otherwise, compared with lead, tungsten alloy is more environmentally friendly，and tungsten alloy is non-toxic and non-radioactive.