Reduced Iron Powder In The Present Society Used Two Methods Of Production
Iron powder is an important raw material in powder metallurgy, industrial production and application of reduced iron powder begins in the 1920 of the 20th century, the production of reduced iron powder method, reduction method and spray method is the main method of production, these two methods of production capacity in the world reduced iron powder in the total production capacity is about half and half.
Reduction method using solid or gaseous reducing agents (Coke, charcoal, anthracite, water coal gas, into natural gas, synthetic ammonia, hydrogen, and so on) reduction of iron oxides (iron ore, rolled steel scales, etc) to produce spongy iron. The restore method. Solid carbon reduction in tunnel kiln production of sponge iron, crushed again with a two-stage furnace with hydrogen reduction method, namely, the Hgans method on the production accounts for an overwhelming majority, the longest tunnel kilns 265 meters long. Annual production capacity of 65000 tonnes of iron powder, iron powder for production of high quality iron > 98. 5%. C ≤ 0. 1%. P and s are less than 0. 3%. Hydrogen loss was 0. 1~0. 2%. In addition. United States useful method of belt furnace for hydrogen reduction of iron scale (pyron), production of low apparent density of iron powder. Soviet useful carbon black joint and common conversion natural gas reduction of iron scale of reduction.
Atomization with high pressure water or air flow current rush to melt iron into a mist. Made of iron powder. This method using furnace melting process. Using steel scrap as raw material. High productivity; however, after atomization desired restore annealing (decarburization oxygen), grinding and subsequent processing in order to get a quality iron. Powder is generally irregularly shaped or nearly spherical. This method often used two methods: ① air atomizing high carbon iron or water flow; low carbon steel flow using a high pressure water spray, high pressure water spray method is widely used, production of iron powder by 1/3 per cent of world output, can also produce fully alloyed low alloy steel powders.
For production powder metallurgical iron products of iron powder, its quality index General including: chemical components as iron, and carbon, and oxygen, and sulfur, and p, and acid not dissolved real content, oxygen content available hydrogen loss (in hydrogen in the restore of loss weight) approximate to said; physical, and process performance, as screening grain degrees composition, and pine loaded density, and liquidity, and compression sex and sintering size stability,. Reduction method and spray method can now produce low oxygen and high compression high quality iron, high compressibility and low oxygen content to produce the high quality iron powder.