Influence of Cryorolling on Spray-Formed Al–Si Alloy

In the present study, the influence of the secondary process, namely cryorolling on microstructure, porosity and hardness of spray-formed Al–Si alloy has been studied. The Al–Si alloys included of 6 wt% of Si have been selected and have been made by the spray forming technique using nitrogen as atomized gas. Further, cryorolling of spray-formed Al–Si alloy has been performed with a different reduction on a rolling mill. The cryorolled spray-formed Al alloy with different reductions has been characterized by different techniques. The X-ray diffractometer (XRD) analysis indicates that the alloy is Al–Si alloy, and no other phases are present. However, microstructure studies indicate that the spray-formed Al–Si alloy consists of equiaxed grains of α-aluminium and Si particles, which refine by cryorolling. The porosity measurement indicates that the value of porosity decreases continuously with an increasing thickness reduction under cryorolling. The hardness has correlated with the porosity and the evolved microstructure of the Al alloy. The 50% cryorolled spray-formed Al–Si alloy exhibits the maximum improvement in properties.