Production of Aluminum/SiC/NiAl<sub>2</sub>O<sub>4</sub> MMCs by Thixoforming of Recycled Chips

Abstract

The work explores the production of Al/SiC and Al/SiC/NiAl 2 O 4 composites by thixoforming compacted mixtures of AA7075 machining chips and reinforcing particles. It is analyzed the influence of processing parameters in the various processing steps, such as mixing, compacting, heating and thixoforming, in the final quality of products. Results showed the general viability of producing composites by the proposed technique; the utilization of recycling material is particularly important in the high demanding energy processing sector, as the Al industry. NiAl 2 O 4 particles and, in less extent, also SiC particles, can penetrate into the liquid phase present in the thixotropic microstructure within the chip, promoting their disaggregation; reinforcement distribution in the composite depends on appropriate choose of processing parameters.