Study of Microstructural and Tribological Properties of LM13 Alloy Composite Foam

Abstract

Closed-cell aluminum foam offers a unique combination of properties such as low density, high stiffness, strength and energy absorption that can be tailored through design of the microstructure. With a view, the goal is to develop superior multifunctional properties in the applications such as wear resistance, electrical components and light weight structural parts in industries including aerospace, automotive and defense. In the present investigation, effect of holding temperatures and amount of reinforcement of zircon sand on the microstructure of LM13 alloy foam and LM13 alloy composite foam has been studied. For this purpose LM13 piston alloy of near eutectic composition is used as foaming matrix material and zircon sand particles as reinforcement. Composite foam was developed by stir casting route at different holding temperatures. Variation in microstructures of the composite foam is observed with the addition of zircon sand particles and also with varying holding temperatures. The results show that the microstructural parameters such as cell size, node and ligament increases with increasing holding temperature which affects the tribological properties of cast materials. The wear rates of the samples were measured under dry sliding conditions with different loads. The wear mechanism was investigated and the effects of the foam cell size on the wear properties were determined. Experimental results indicate that reinforcement upto 5% zircon sand enhances the properties like hardness and wear characteristics of the formed foams. Moreover, the cell size and nodes are optimum which is responsible for such a enhanced property.