Fabrication of fiber reinforced metal matrix composites by squeeze casting technology

Squeeze forming process is a special casting technique that combines the advantages of traditional high pressure die casting, gravity permanent mold die casting and common forging technology. It is a relatively new casting process. It is otherwise called squeeze forming, liquid forging, liquid pressing, extrusion casting, liquid metal stamping, pressure crystallization and corthias casting. The above said process was first discovered by the Russians and later it was developed in countries like USA, Europe and Japan. This advanced casting method is applied for processing of both ferrous and non-ferrous materials besides composites. The major advantages of this technology are elimination of porosity and shrinkage, 100% casting yield, attainment of greater part details, good surface finish, good dimensional accuracy, high strength to weight ratio, improved wear resistance, higher corrosion resistance, higher hardness, resistance to high temperature, improved fatigue and better creep strength. The components manufactured by this casting method requires lesser post machining operation and they have improved mechanical properties like higher strength and ductility. In squeeze casting process the liquid metal is pressurized while they solidify and hence near net shapes can be produced with sound and dense quality. The microstructural refinement of squeeze cast products is desirable for many critical applications. This process is simple, economical and it can be automated easily. The process generates the highest mechanical properties attainable in a cast product. So this process has been adopted to make composite castings at an affordable cost. This paper reviews about the principles of squeeze casting technology, which can be applied to process discontinuous fiber reinforced metal matrix composite castings. Besides this article highlights the type of engineering components produced by this advanced casting method.(c) 2005 Elsevier B.V. All rights reserved.