Tungsten steel (hard alloy) has high hardness, wear resistance, strength and toughness is good, heat resistance, corrosion resistance and a series of excellent properties, especially its high hardness and wear resistance, even at 500℃ temperature is basically unchanged, at 1000℃ still has a high hardness.
Tungsten steel, also known as hard alloy, is a sintered composite material consisting of at least one kind of metal carbide. Tungsten carbide, cobalt carbide,
niobium carbide,
titanium carbide and tantalum carbide are common components of tungsten steel. Carbide components (or phases) typically have grain sizes between 0.2 and 10 microns, and carbide grains are held together using metal binders. The binder usually refers to the metal cobalt (Co), but for some special purposes,
nickel (
Ni), iron (Fe), or other metals and alloys may also be used. The composition of an undetermined carbide and bond phase is called "grade".
Tungsten steel is classified according to ISO standards. This classification is based on the material type of the workpiece (such as P,M,K,N,S,H grades). The bonding phase composition is mainly made use of its strength and corrosion resistance.
The matrix of tungsten steel consists of two parts: one is hardened phase; The other part is the bonding metal. Bonding metals are generally iron group metals, commonly used is cobalt, nickel. Hence tungsten-cobalt, tungsten-nickel and tungsten-titanium-cobalt.
For steel containing tungsten, such as high speed steel and some hot-work die steels, the presence of tungsten in steel can significantly improve the hardness and heat resistance of the steel, but the toughness of the steel decreases dramatically.
The main application of tungsten resources is also hard alloy, namely tungsten steel. Cemented carbide, known as the teeth of modern industry, tungsten steel products are widely used.
The main problems existing in China's cemented carbide industry are as follows: first, the enterprise scale is small and the industrial concentration is not high. According to incomplete statistics, the average annual production capacity of 199 cemented carbide enterprises is 176 tons, the average annual output is only 86 tons, and there are only 4 enterprises with the annual output of more than 1,000 tons. Second, less investment in science and technology, lack of high-end technical personnel, technology research and development capacity is weak. The investment in science and technology of cemented carbide industry in China is less than 3% of sales revenue, the level of science and technology research and development is not high, and the original core technology achievements are few. Third, the product quality level is low, the product structure needs to be adjusted. China's cemented carbide production accounts for more than 40% of world output, but the carbide sales income is less than 20% of the world, mainly due to the high performance super fine alloy coating, high precision, high performance grinding blade, ultra hard tool materials, complex, precision carbide nc cutter large products less high value-added products production, deep processing and varieties of form a complete set is not complete.
With the rapid expansion of China's auto industry, the demand for cutting tools for auto parts processing is increasing, and the demand for cemented carbide in China's iron and steel, transportation, construction and other fields is also growing. In the strategic picture of foreign cemented carbide multinational companies, The Chinese market has quietly changed from a supporting role to a leading role.
According to the analysis, by the end of the 12th Five-Year Plan, China's cemented carbide output reached 30,000 tons, sales revenue reached 30 billion yuan, and the output of deeply processed products accounted for more than 40% of the total cemented carbide. Compared with the 11th Five-Year Plan, the export will double and strive to exceed 1 billion US dollars. Cemented carbide will develop towards the direction of intensive and deep processing and supporting tools. To the ultra-fine, ultra-coarse and coating composite structure direction; To circular economy, energy conservation and environmental protection; To the precise, miniaturized direction of development.
