In the process of making a part by powder metallurgy, powders of metals or metal oxides are blended together sometimes with additional binders, fluxes, or lubricants. The final mixture is poured into a die and forced together by high pressure. The part may be heated while pressing or placed in a furnace afterward. Surface melting causes the grains of metals to alloy and bond, producing a solid part.
Powder metallurgy has several advantages over normal alloying processes. Dissimilar metals that would normally segregate due to differences in density or melting point can be forced to alloy. Additional metals that do not bond can be caught in the matrix and influence the bulk properties of the material. Varying the temperature or pressure during fabrication can also affect material properties. Parts can be forged to final or almost final shape, eliminating costly machining.
The Surface Processing and Mechanics has been investigating two areas of study in powder metallurgy. The group has been fabricating interface coatings between the seal coat and composite in turbine systems. The second focus of the group has been the production of small arms ammunition for military and police use.
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