Aluminum powder metallurgy

The applications of aluminum are growing larger and more varied with tile introduction of advanced materials engineering techniques, including sandwich-type construction, laminates, aluminum powder metallurgy, and composite technology,... 

Aluminum powder metallurgy continues to receive high research and development priority. A major objective is to produce final aluminum parts by direct pressing of rapidly solidified aluminum particles. The process handles high-strength aluminum alloy materials. 

Pickens, J. R., Review Aluminum Powder Metallurgy Technology for High-Strength Applications, Journal of Materials Science, Vol. 16, 1981, pp. 1437-1457. 

Metallurgy aluminothermic production of chromium metal by reaction of aluminum powder and Cr203... 

Meial Mairix Composites. Silicon carbide particles are contributing to easy-to-cast metal-matrix composites (MMCs). When compared with their non-reinforced counterparts, the SiCp/Al components are more wear resistant, stiffer, and stronger, accompanied by improved thermal stability. Additional advantages include lower density and lower cost. Nearly all prior aluminum MMCs required labor-intensive methods, such as powder metallurgy, diffusion bonding, squeeze casting, or thermal spraying. 

A hi mi nidcs. These are intermetalhc compounds of aluminum. The potential of these products includes uses where low weight, high-temperature strength, and oxidation resistance are required. Traditionally, these products are made by way of powder metallurgy technology. 

The term cermet derives from the combination of ceramic and melal. Cermets are produced by powder metallurgy techniques and represent Ihe bonding of two or more metals. They are particularly useful at high temperatures (850- I250"C). Chromium is used in several cermet combinations, including chromium-bonded aluminum oxide, metal-bonded chromium carbide, and metal-bonded chromium horide. 

POWDER METALLURGY. Powder metallurgy (PM) embraces the production of finely divided metal powders and their union through the use of pressure and heat into useful articles. The temperatures required are below the fusion point of the principal constituent, and bonding depends on interdiffusion of the metal particles in the solid state. It is necessary to provide intimate contact between particles, hence reducing atmospheres are provided in the sintering process to prevent formation of oxide films Readily oxidized powders such as aluminum require special technique. 

B. H. Rabin, R. L. Williamson, R. J. Heaps and A. W. Erickson, "Powder Processing of Nickel-Aluminum Oxide Gradient Materials" pp. in press in PM 92, Proceedings of the 1992 Powder Metallurgy World Congress. Edited by Metal Powder Industries Federation, Princeton, NJ, 1992. 

Neikov, O.D. (2000) Water Atomized Powder Technologies for Advanced Aluminum Alloy Production. Proc. of 2000 Powder Metallurgy World Congress, Kyoto, Japan, part 1, 464-466. 

Processing of Powder Metallurgy Alloys. Powder metallurgy processed aluminum alloys suffer from three major microstructural problems that limit their full potential prior-particle boundaries with an aluminum oxide film, microstructural inhomogeneity, and remnant porosity. These microstructural features particularly hamper the ductility in very high-strength aluminum alloys. Berbon et al. (Ref 59, 134)... 

Domack, M. S., Stress Corrosion Evaluation of Powder Metallurgy Aluminum Alloy 7091 with the Breaking Load Test Method, Presented at the Tri-Service Corrosion Conference, Colorado Springs, CO, 5-7 May 1987, p. 21... 

Hayajneh, M.T., Hassan, A.M. and Mayyas, A.T. (2009) Artificial neural network modeling of the drilling process of self-lubricated aluminum/alumina/graphite hybrid composites synthesized by powder metallurgy technique, J Alloys Compd, 478 559-65. 

Baghchesara, M.A., Abdizadeh, H., Baharvandi, H.R., 2012. Effects of MgO nano particles on microstmctural and mechanical properties of aluminum matrix composite prepared via powder metallurgy route. International Journal of Modem Physics Conference Series 607-614. 

Special aluminum products. In recent years, a number of new aluminum alloys have been developed. For example, the powder metallurgy route can be a cost-effective method for manufacturing components with conventional aluminum alloys, especially for small parts requiring close dimensional tolerances (e.g., connecting rods for refrigeration compressors). But this process is still relatively expensive. Rapid solidification and vapor deposition processes permit production of aluminum alloys with compositions and microstructures that are not possible by conventional cast or wrought methods. 

Other tests have shown that the residual AP+ and Fe + ions present in red muds can be made into inexpensive flocculants for sewage treatments, which are also particularly efficient at removing phosphate [25]. When processed to a finely divided dry powder, this can be used as a pigment, or can yield aluminum, iron, and titanium by reduction metallurgy [25]. In these ways salable commodities may be obtained from a process waste material. 

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