Investigation of impact behaviour of aluminium based SiC particle reinforced metal–matrix composites

In this paper, the impact behaviour of aluminium and silicon carbide (SiC) particle reinforced aluminium matrix composites under different temperature conditions was determined. Charpy impact tests were performed on as extruded and heat treated specimen at temperatures varying from −176 to 300 °C. Composite specimens based on aluminium alloys of 2124, 5083 and 6063 and reinforced by SiC particles were manufactured. Two different SiC sizes of 157 μm and 511 μm and two different extrusion ratios of 13.63:1 and 19.63:1 were used. The results of instrumented impact tests were compared with the microstructural and fractographic observations. The failure mechanisms and deformation behaviour of unreinforced alloys and composites were assessed. The impact behaviour of composites was affected by clustering of particles, particle cracking and weak matrix-reinforcement bonding. Agglomeration of particles reduced the impact strength of Al 2124 and 6063 based composites. Alumınum 6063 alloys and composites showed a better impact strength. The impact strength of 6063 composites increased with particle size and extrusion ratio. The effects of the test temperature on the impact behaviour of all materials were not very significant.