Recycling of discontinously reinforced aluminum-matrix composites by an innovative gaseous process.

A. E. BOHÉ; H. E. NASSINI

Madrid, Spain.

Simposio; Rewas 04´. Global Symposium on Recycling Waste Treatment and Clean Technology.; 2004

TMS-Mineral-Metals –Materials e INASMET-European Commission, INPL-Nancy France and The Minning and Materials Processing of Japan

Aluminum Metal Matrix Composites (MMCs) with discontinuous ceramic reinforcement of short fibers, whiskers, and particles have emerged as a novel class of materials for structural, aerospace, automotive and thermal management applications. Since the expensive ceramic reinforcements contribute significantly to the final cost of aluminum MMCs, the feasibility of their recovery from the composite scrap and further recycling is a factor of increasing economic interest. The chlorination process is an attractive and efficient method for separating metals from complex materials, allowing to turn all the metals contained in the materials into their respective chlorides which are further separated in a selective way. In the present work, the feasibility of recovering Al2O3 and SiC particles from two commercially available aluminum MMCs is demonstrated, both theoretically and experimentally. The process consists of transforming the constituents of metallic alloy matrices in gaseous chlorides that are dragged by the gaseous stream, while the ceramic reinforcement remains as a solid residue in the reaction bed.