What are the classifications of nonferrous metals?

In practical application, non-ferrous metals are usually divided into five categories:

1, light metal. The density is less than 4500kg/m3 (0.53 ~ 4.5g/cm? ), such as aluminum, magnesium, potassium, sodium, calcium, strontium, barium and so on.

2. Heavy metals. The density is greater than 4500 kg/m3 (4.5 g/cm? ), such as copper, nickel, cobalt, lead, zinc, tin, antimony, bismuth, cadmium and mercury.

3. Precious metals. It is more expensive than common metals, with low crustal abundance, difficult to purify and stable in chemical properties, such as gold, silver and platinum group metals.

4. Semi-metal. Properties between metal and nonmetal, such as silicon, selenium, tellurium, arsenic and boron.

5. Rare metals. Include rare light metals such as lithium, rubidium, cesium, etc. Rare refractory metals, such as titanium, zirconium, molybdenum, tungsten, etc. Rare dispersed metals such as gallium, indium and germanium; Rare earth metals such as scandium, yttrium and lanthanide metals; Radioactive metals, such as radium, francium, polonium, uranium and thorium in series elements.

Extended data:

The nonferrous metal industry in old China was extremely backward, and most of it was exported in the form of ore, while rich nonferrous metal resources were buried underground. After the founding of People's Republic of China (PRC), the nonferrous metal industry developed rapidly. By 1998, there were 437 non-ferrous metal mining and dressing enterprises independently accounted for in eight ethnic minority areas, creating an output value of15150,000 yuan, accounting for nearly 32% of the total national non-ferrous metal output value.

There are 262 independent accounting enterprises for nonferrous metal smelting and calendering, with an output value of 5. 93 billion yuan. It has formed a relatively complete industrial system from exploration, mining, beneficiation and metallurgy to processing. There are many kinds of nonferrous metals, but there are many kinds of copper, aluminum, lead, zinc, tin and magnesium commonly used in industry.

Nonferrous metals are essential basic materials and important strategic materials for national economy, people's life, national defense industry and scientific and technological development. Agricultural modernization, industrial modernization, national defense and scientific and technological modernization are all inseparable from non-ferrous metals.

Such as aircraft, missiles, rockets, satellites, nuclear submarines and other sophisticated weapons, as well as parts or components required for advanced technologies such as atomic energy, television, communications, radar and electronic computers, are mostly made of light metals and rare metals among non-ferrous metals.

In addition, if there were no nonferrous metals such as nickel, cobalt, tungsten, molybdenum, vanadium and niobium, there would be no production of alloy steel. Non-ferrous metals are also used in some applications (such as power industry). Many countries in the world, especially industrialized countries, are competing to develop the non-ferrous metal industry and increase the strategic reserve of non-ferrous metals.

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