Thixoforming and Powder Metallurgy - A Comparative Study and Practical Case

Abstract:

Pistons are commonly made of a cast aluminum alloy for excellent and lightweight thermal conductivity. Thermal conductivity is the ability of a material to conduct and transfer heat. Aluminum expands when heated and proper clearance must be provided to maintain free piston movement in the cylinder bore. The piston transforms chemical energy of the burned fuel into a mechanical energy. For this reason, the pistons are submitted to a complex combination of thermal stresses and high temperature mechanical cycles. In this study both powder metallurgy (PM) and thixoforming techniques are used to process a metallic matrix composite (MMC) as a promising material for pistons. Aluminum as matrix and copper powder, to enhance thermal conductivity, and glass fiber, which increases Young’s modulus and a lower thermal expansion coefficient, as reinforcement, are obtained for this aim. The optical microscope images showed in this study are a clear example of the distribution of the glass fiber in the matrix. These results can be the basis for new researches to develop and to obtain materials for new advanced materials for pistons.

• Periodical: Materials Science Forum (Volume 907)
• Pages: 193-197
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.907.193
• Online since: September 2017
• Authors: Samuel Gallego Parra, Mihai Alin Pop*, Tibor Bedő, Virgil Geamăn
• Keywords: Metallic Matrix Composite, Piston, Powder metallurgy, Thixoforming

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