Reduction of OxidesThe major world producer of iron powder manufactures powder by the reduction of iron oxide either in the form of a pure iron ore, or as pure mill-scale from a large rolling mill. In either case an irregular, spongy powder is produced, with a particle size of minus 100 mesh, that is the…
1. Powder Metallurgy Is a Green Manufacturing Process About 97% of the material that enters the powder metallurgy process exits as part of the final product. Good luck finding similar net shape capabilities in any other manufacturing processes. This means very little waste and scrap. Powder metallurgy (PM) is a win-win for your wallet and the environment. Other metal…
Producing metal parts by machining is inherently wasteful. Your vendor expends energy turning metal into chips, which get scrapped and perhaps remelted. Clearly, a net shape or near-net shape process like powder metallurgy has many advantages — not the least of which is saving on material costs. However, there are situations where die constraints mean parts…
Molten steel being transferred into a ladle prior to atomisation (Courtesy Epson Atmix Corporation, Japan) Iron powder production In tonnage terms, the production of iron powders for PM structural part production dwarfs the production of all of the non-ferrous metal powders combined. Virtually all iron powders are produced by one of two processes. The sponge…
With powder metallurgy, you identify your powder of choice and your vendor pours it into the die, which is shaped as the mirror image of your design. Since you can control where you put the powder and how much, when it’s compacted it turns out exactly how you want the final version to look. The part…
When most people think of the metal-making process, they picture a stream of molten metal pouring into a mold — it makes a nice visual for films and commercials. But when you consider making parts with powder metal, it may be a little harder to picture the process — or why one would bother with powder metal…
The first step in the overall powder metallurgy (PM) process is making metal powders. There are four main processes used in powder production: solid-state reduction, atomization, electrolysis, and chemical. Solid-State Reduction In solid-state reduction, selected ore is crushed, typically mixed with carbon, and passed through a continuous furnace. In the furnace, a reaction takes place,…
Metals occur in nature sometimes in free or native state, but most of these occur in nature in the form of chemical combination, i.e., in the form of their stable compounds which are associated with gangue or matrix. The earthy impurities such as sand, clay, rocks etc. associatedwith ore are collectively known as gangue or matrix. Thus a large number of metals in nature…
(a) Electrolytic refining This is one of the most convenient and important method of refining and gives a metal of high purity. This method is applicable to many metals such as Cu, Ag, Pb, Au, Ni, Sn, Zn etc. The blocks of impure metal form the anode and thin sheets of pure metal form the cathode. A…
The ore is generally associated with rock impurities like clay, sand etc. called ‘ gangue or matrix‘. The purification of ore means removal of gangue from the powdered ore. This process is otherwise called concentration of the ore or ore dressing. Thus, the percentage of the ore in the concentrated ore is higher than that in…