Recycling of composite casts reinforced with aluminosilicate sinter
Dorota Nagolska Politechnika Poznańska, Instytut Technologii Materiałów, ul. Piotrowo 3, 61-138 Poznań, Poland
Quarterly No. 4, 2008 pages 409-413
DOI:
keywords: recycling, metal composite casts, reinforcement structure
abstract Metal composites with saturated reinforcement belong to the group of materials that, due to their properties, is more and more commonly used, particularly in the automotive industry. Nevertheless, during their usage the composite components, among others the matrix metal, are subject to degradation. This precludes their secondary use without additional improvement (refining) processes that may be carried out only upon separation of the composite components. The research of metal composites manufactured by saturation of a sintered graphite reinforcement with a liquid metal matrix has shown that the process of separation of the components is extremely difficult. Results of the research were conducive to the question whether the use of other sinters as composite reinforcement gives rise to the same troubles while recycling the composite material. Since the knowledge of surface properties simplifies comparison of the analyzed systems, as a subject of the research were chosen the composites reinforced with aluminosilicate sinter, aluminium EN AC-AlSi12(b), and lead OT7, but of various porosities of reinforced profiles. Afterwards, the composites were recycled in the environment of air and melted salt mixture. Results of the research have shown that for properly selected conditions of the process according to the relationship (1) the composites reinforced with aluminosilicate sinter (Fig. 4) may be readily recycled with the method of intrinsic metal outflow from the reinforcement pores, as opposed to ones with graphite sinter reinforcement. They also suggest that according to current knowledge separate studies should be carried out for each of the composite groups in order to determine optimal recycling conditions. Moreover, reinforcement porosity may be one of the factors decisive for the recycling process.