Development of Novel Al-based Metal Matrix Complex Nanocomposites by Different Reinforcement Strategies

M. GALANO; F. AUDEBERT; N. ROUNTHWAITE; A. KNOWLES; X. JIANG

Shanghai

Congreso; International Conference on Rapidly Quenched and Metastable Materials, RQ15; 2014

The demand of the development of light weight alloys that can achieve high strength at elevated temperatures has been increasing substantially in the Automotive and Aerospace sectors for several years. Nowadays, due to the tighter restrictions for carbon emissions the industrial needs request new alloys or composites that achieve improvements of combined properties such as light weight, strength with temperature toughness, stiffness etc. has become a priority. The present work is based on the development of novel Aluminium alloys matrix nanocomposites with combinations of reinforcement strategies at the nanoscale to target specific applications. Nanoreinforcements such as nanosize quasicrystalline and ceramic particles or pure metals as plasticizers have been used in combination of a nanostructured Al based alloys matrixes to generate innovative Al metal matrix composites Several powder metallurgy techniques have been applied in the manufacturing of the different nanocomposites particularly the ones containing ceramic reinforcements were processed using ball milling techniques. Composites were manufactured severe plastic deformation processes such as extrusion and in some cases followed by rolling. The extrusion process on the nanocomposites containing plasticizers produces anisotropic composites with ductile fibres which improve ductility and toughness. Subsequent rolling has shown the enhancement of the strengthening properties of simple composites. The structural characterization was performed using XRD including texture XRD, electron microscopy techniques SEM and TEM combined with EBSD and EDX. Complimentary, calorimetric analysis has been used in order to study the microstructural stability. The mechanical behaviour of the different nanocomposites has been studied and compared to high strength commercial Al alloys achieving a template of nanocomposites with an improved combined behaviour of mechanical properties as a function of the processing method. The relationship between processing, microstructure and properties drawn in this work will inform further understanding and optimisation of these and other nanocomposite systems.