1. Non ferrous metals
Tungsten is a non-ferrous metal. Usually people divide metals into two categories according to their color and properties: ferrous metals and non-ferrous metals. Ferrous metals mainly refer to iron, manganese, chromium and their alloys, such as steel, pig iron, ferroalloy, cast iron, etc. Metals other than ferrous metals are called non-ferrous metals. Tungsten belongs to the category of non-ferrous metals. The strength and hardness of non-ferrous alloy are generally higher than that of pure metal, the resistance is larger than that of pure metal, the resistance temperature coefficient is smaller, and it has good comprehensive mechanical properties. Therefore, as a non-ferrous metal, tungsten has very high strength and hardness. Due to this characteristic, tungsten carbide with high hardness and strong wear resistance is widely used in cutting tools and mining tools.
2. Refractory metal
Tungsten is the refractory metal with the highest melting point. Generally, the metals with melting point higher than 1650 ℃ and certain reserves, and the metals with melting point higher than zirconium (1852 ℃) are called refractory metals. Typical refractory metals are tungsten, tantalum, molybdenum, niobium, hafnium, chromium, vanadium, zirconium and titanium. As a refractory metal, the most important advantage of tungsten is that it has good high temperature strength and good corrosion resistance to molten alkali metal and steam. Only when the temperature of tungsten is above 1000 ℃, can oxide volatilization and liquid phase oxide appear. However, it also has the disadvantage of high plastic brittle transition temperature, which makes it difficult to plastic process at room temperature. The refractory metals represented by tungsten are widely used in metallurgy, chemical industry, electronics, light source, mechanical industry and other sectors.
3. Rare metals
Tungsten is a rare metal. Rare metals usually refer to the metals with less content or scattered distribution in nature. Tungsten is a widely distributed element, which can be found almost in all kinds of rocks, but its content is relatively low. The content of tungsten in the earth's crust is 0.001%, and that in granite is 1.5 × 10-6 on average, which makes it very difficult to extract. Generally, only organic solvent extraction and ion-exchange method can be used to separate and extract tungsten.  With the development of science and technology
With the development of metallurgical technology, equipment, analysis and detection technology and the expansion of production scale of rare metals, the purity of tungsten is constantly improved, performance is constantly improved and varieties are constantly increased, thus expanding the application field of tungsten. China is rich in tungsten resources, and its output and total export amount account for the first place in the world.