Tungsten Filamenttungsten Rodtungsten Platetungsten Tungsten Bolttungsten Crucibletungsten Sheettungsten Standard Partstungsten Stamping Partpure Tungst

Tungsten alloy is a kind of tungsten based (tungsten content of 85% ~99%), and add a small amount of Ni.Cu, Fe. Co. Mo, Cr and other elements of the alloy, its density is up to 16.5~ 18.75g/cm3, known as high specific gravity alloy, heavy alloy or high density tungsten alloy.Tungsten alloy is widely used in electronics and electric light source industry, and is also used in aerospace, casting, weapons and other sectors to make rocket nozzle, die casting mold, armor piercing core, contacts, heating body and heat shield. Molybdenum tungsten alloyAn alloy containing two elements, molybdenum and tungsten, including molybdenum based molybdenum tungsten alloy and tungsten based tungsten molybdenum alloy series. The alloy can be formed in any proportion and is a complete solid solution alloy at all temperatures.Niobium tungsten alloyA niobium alloy based on niobium formed by adding a certain amount of tungsten and other elements. Tungsten and niobium form infinite solid solutions. Tungsten is an effective strengthening element of niobium, but with the increase of tungsten addition, the plasticity and brittleness transition temperature of the alloy will rise, and the grain will grow significantly. Therefore, in order to obtain high strength niobium tungsten alloy, it is necessary to properly control the addition of tungsten, and at the same time, it is necessary to add appropriate amount of elements such as zirconium and hafnium to refine the grain and reduce the plastic-brittle transition temperature. In 1961, the United States successfully developed Nb-10W-2.5Zr alloy for the skin of the space shuttle, and later developed into Nb-10W-1Zr-0.1C alloy. In the early 1970s, China also successfully developed NbWl0Zr2.5 and NbWl0Zr1C0.1 alloys.Hard metal alloyHard alloy is the most common and main form of tungsten alloy. Unlike the previous tungsten alloys, it is tungsten, carbon and cobalt, so it is often called tungsten-cobalt alloy. The most widely used tools in the industrial field are basically carbide tools, so carbide this tungsten alloy is also known as "industrial teeth".Development history editorIn 1907, a tungsten alloy with low nickel content was introduced. It was prepared by mechanical processing, but severe brittleness prevented its application. It was not until 1909 that W. D. Coolidge of General Electric Company in the United States made tungsten billet by powder metallurgy and then mechanically processed it to produce tungsten wire with ducibility at room temperature, thus laying the foundation of tungsten wire processing industry as well as powder metallurgy.However, this "ductile" tungsten alloy shows significant brittleness after the light bulb is lit. In 1913, Pintsch invented thorium tungsten filament (ThO2 content of 1% to 2%), which greatly reduced the brittleness of the incandescent filament. At first, the droop of the filament was not a problem, because the filament was straight at that time. However, after 1913, Langmuir changed the straight filament into spiral filament. In this way, when the bulb was used, the high working temperature and dead weight made the filament droop, so it was difficult for both pure tungsten and thorium tungsten to meet the application requirements.In order to solve the problems of sagging tungsten wire and short life, in 1917, A. SPZ invented tungsten alloy with "no deformation" at high temperature. At first, he used a refractory crucible to roast WO3 when preparing pure tungsten. He accidentally found that the tungsten wire spiral made from the tungsten powder reduced by such WO3 mysteriously did not sag after recrystallization. Subsequently, after 218 times of repeated experimental verification, he finally found that in tungstic acid (WO3·H2O) adding potassium and sodium silicate, after reduction, pressing, sintering, processing and so on to make tungsten wire, recrystallization to form a very coarse grain structure, neither soft and anti sagging, this is the earliest non-sagging tungsten wire. Beth's discovery laid the foundation for the production of undrooped tungsten wire, which is still called "218 tungsten wire" in the United States, in honor of Beth's discovery.The production process of doped tungsten alloy is lengthy, including tungsten smelting, powder metallurgy and plastic processing.Ammonium paratungstate (APT) is usually used as raw material in the production of doped tungsten alloys. In addition to the traditional classical process, the extraction method and ion exchange method were studied internationally in the 1950s, and these processes were also adopted in China in the 1970s, thus simplifying the process flow and improving the recovery rate of tungsten. Since the 1960s, many countries have adopted blue tungsten oxide doping process to replace tungsten trioxide doping, so as to improve the doping effect. Pickling of tungsten powder began to be applied to production in the 1960s, its main purpose is to wash away the excess dopant, ultrafine powde