What do you know about the main uses of tungsten?
Tungsten has the highest melting point of all metal elements and a very high density (19.3 g/cm³), which is close to gold. Tungsten also has a high hardness, such as tungsten carbide, which is close to diamond. In addition, tungsten also has good electrical and thermal conductivity, small coefficient of expansion and other characteristics, so it is widely used in alloy, electronics, chemical industry and other fields, among which hard alloy is the largest tungsten consumption field.
alloys
Iron and steel
Tungsten hardness is high, the density of tungsten is close to gold, and thus can improve the strength of steel, hardness and wear resistance, is one of the important alloy elements, are widely used in various kinds of steel production, common containing tungsten steel has high speed steel, tungsten steel, and has high magnetization and coercive force of tungsten cobalt magnetic steel, etc., these steel products mainly used in the manufacture of a variety of tools, Such as drill, milling cutter, wire drawing die, Yin die and Yang die.
Tungsten carbide base carbide
Tungsten carbide has high wear resistance and refractoriness, and its hardness is close to that of diamond, so it is often used in some hard alloys. At present, tungsten carbide base carbide is the largest consumption of tungsten, this kind of hard alloy is tungsten carbide micron powder and metal adhesives (such as cobalt, nickel, molybdenum) sintered in vacuum furnace or hydrogen reduction furnace into powder metallurgy products. Tungsten carbide base carbide is generally divided into tungsten carbide - cobalt, tungsten carbide - titanium carbide - cobalt, tungsten carbide - titanium carbide - tantalum carbide (niobium) - cobalt and steel bonded carbide and other four categories, these tungsten carbide base carbide is mainly used in the manufacture of cutting tools, mining tools and wire drawing die.
Thermal strength and wear resistant alloy
Tungsten has the highest melting point of all metals and is also very hard, so it is often used to produce heat and wear resistant alloys. For example, tungsten and chromium, cobalt and carbon alloys are commonly used to produce high strength and wear resistant parts, such as the valve of aero-engine and turbine impeller. Alloys of tungsten and other refractory metals, such as tantalum, niobium, molybdenum and rhenium, are often used to produce high thermal strength parts such as jet nozzles and engines for aerospace rockets.
High specific gravity alloy
Due to its high density and hardness, tungsten has become an ideal material for making high specific gravity alloys. These high specific gravity alloys are divided into W-Ni-Fe, W-Ni-Cu, W-Co, W-WC-Cu, W-Ag and other main series according to their composition characteristics and uses. This kind of alloy has the characteristics of heavy specific, high strength, strong ray absorption ability, high thermal conductivity, small thermal expansion coefficient, good electrical conductivity, weldability and good processing, and is widely used in aerospace, aviation, military, oil drilling, electrical instruments, medical and other industries. Such as making armor, heat sink, balance hammer to control rudder and contact materials such as knife switches, circuit breakers, spot welding electrodes, etc.
Electronics field
Tungsten and its alloys are widely used in electronics and power supply industries because of its strong plasticity, low evaporation rate, high melting point and strong electron emission ability. For example, tungsten wire has high luminous rate and long service life, so it is widely used in the manufacture of various bulb filaments, such as incandescent lamp, iodine tungsten lamp, etc. Tungsten wire can also be used in the manufacture of electronic oscillating tubes of the direct hot cathode and gate as well as a variety of electronic instruments in the side hot cathode heater. The properties of tungsten also make it suitable for TIG welding and other similar electrode materials.
Field of chemical industry
Tungsten compounds are commonly used as catalysts and inorganic colors. For example, tungsten disulfide is used as a lubricant and catalyst in the preparation of synthetic gasoline, bronze tungsten oxide is used in painting, and calcium or magnesium tungsten is commonly used in phosphors.
In other areas
Because tungsten's thermal expansion is similar to boron silicate glass, it is used to make glass or metal seals. Tungsten is used to make high purity tungsten gold jewelry because of its low sensitivity. In addition, tungsten is used in radiation medicine, and in the chords of some Musical Instruments.
