Tungsten is a rare precious metal, since 1783 was discovered scientists, has been 200 years of history. According to estimates, the content of tungsten in the earth's crust is one in a million. China's tungsten reserves account for about 60% of the world's total reserves, ranking first in the world. It can be said that China is a well-deserved kingdom of tungsten. Roots Vacuum Pump For Mining Industry Big Roots Blower,3 Lobes Roots Blower,Roots Blower Vacuum Pump,High Vacuum Diaphragm Pump Shandong Heli Machinery Co.,Ltd , https://www.chinaheliblower.com
Tungsten has excellent properties such as high specific gravity, high melting point, high hardness, good thermal conductivity, heat resistance, wear resistance, corrosion resistance and chemical stability. The melting point of gold is 1000 degrees Celsius, while the melting point of tungsten is as high as 3380 degrees Celsius. Many of today's high-tech products, such as aerospace jet engines, rockets, missiles, and satellites, are made of high-temperature alloys of tungsten.
In adding tungsten steel inside, like eating a "physical tonic" than steel. Tungsten steel can improve the high temperature strength of steel and increase the hardness and corrosion resistance of steel. It is widely used in metal cutting tools, as well as heat-resistant and pressure-resistant parts of weapons, equipment, guns, tanks and other weapons in the military industry. Therefore, people also regard tungsten as an important strategic metal.
Tungsten has a high hardness and is one of the best in metals. However, tungsten and carbon compounds, tungsten carbide, have higher hardness and are harder than tungsten steel, which is comparable to the hardest diamond in nature. The hard alloy made of tungsten carbide powder has the advantages of high hardness, good wear resistance and high temperature resistance. It can be used for metal cutting tools, drilling rigs , drill bits, blade cutters for bulldozers, crushing machines, etc., even for small dentists. The drill bit is also made of cemented carbide.
The filaments and high-temperature electric wires in the bulbs that people use every day are also inseparable from tungsten. Tungsten's thermal electron emission performance is also excellent, so it is an important material for the production of communications, broadcasting, television, radar and other equipment. The fluorescent materials of TV tubes, X-ray screens, and fluorescent lamps are also selected from tungsten compounds. In addition, tungsten has a vast world in light industry such as textiles, dyes, paints, ceramic glazes, and glass coloring.
In nature, there are more than 20 kinds of tungsten minerals, but industrially only black tungsten ore and scheelite CaWo4. Therefore, there are also black ore ore, scheelite ore and mixed ore of scheelite and scheelite. The long-term development and utilization of scheelite in foreign countries, while China has more than 3 million tons of reserves of scheelite, accounting for 65% of the national tungsten reserves, and 19% of mixed ore, but due to China's white tungsten The ore grade is low, the rich ore is less, and the smelting technology has not been completely solved. Therefore, the long-term mining in China is still a high-grade, easy-to-harvest and easy-to-select black tungsten ore.
Physical properties of tungsten