Production of near net shape thin strips using vertical twin roll casting method has been studied. In a typical VTRC process, the simultaneous action of solidification and rolling makes the process quite attractive as well as complicated. An industrially popular alloy A356 has been chosen for the VTRC processing. It is challenging to identify VTRC processing parameters for the alloy to produce thin strips because of its freezing range and complex composition. In the present work processing parameters of VTRC like roll speed, roll gap, melt superheat and the interface convective heat transfer coefficient have been investigated through modelling of the process. The mathematical model was developed which simultaneously solves the heat transfer, fluid flow and solidification, using commercial software COMSOL Multiphysics 5.4. VTRC sheets of alloy A356 were produced in an experimental set up and attempts were made to correlate the microstructures of VTRC A356 alloy to that predicted from the numerical studies to validate the model.

The study aims to investigate the effect of semisolid structure and strontium (Sr) addition on the wear behavior of hypoeutectic Al-Si alloy. Semisolid hypoeutectic Al-Si alloy was prepared using cooling slope casting with addition of 0 to 0.93 wt.% Sr. Microstructural study was done using an optical microscope. Vicker microhardness and pin on disc tribometer were used for microhardness and wear testing. When compared to conventional casting, the microhardness of the semisolid hypoeutectic Al-Si alloy improved by 9.8%. Sr addition at 0.43 wt.% resulted in a refined eutectic structure with a 17% increase in hardness over conventional casting. The globular structure α-Al formed during semisolid casting reduced porosity, and the addition of Sr refined the eutectic silicon into a fine fibrous structure that is tightly bound with the Al matrix. These are the primary factors that contribute to the high wear resistance in modified-Sr semisolid alloys.