Study on thermal and mechanical properties of yttrium tungstate-aluminium nitride reinforced aluminium matrix hybrid composites

Aluminium matrix hybrid composites (AMHCs) containing 30 wt % Y2W3O12 - (0, 5, 10, 15 wt %) AlN and 30 wt % AlN - (0, 5, 10, 15 wt %) Y2W3O12, defined as Y2W3O12 and AlN rich composites, respectively, were prepared by high energy ball milling followed by compaction, sintering and forging. The hardness, compressive strength, coefficient of thermal expansion (CTE), thermal conductivity and thermal stability of all the composites were evaluated. A high compressive strength (500-520 MPa) along with a low CTE (12-14 × 10−6 K−1) is achievable in such hybrid composites by adjusting the amount of individual reinforcement. The thermal cycling experiments suggest that the composites are thermally stable. The thermal conductivity of the Y2W3O12 rich composites increases with an addition of AlN, whereas it decreases in the AlN rich composites with an addition of Y2W3O12.