Taguchi Approach for Optimization of Parameters that Effect Grain Size of Cast A357 Alloy

Abstract

Grain refining and modification are common foundry practice for improving properties of cast Al-Si alloys. In general, these types of treatments provide better fluidity, decreased porosity, higher yield strength and ductility. However, in practice, there are still some discrepancies on the reproducibility of the results from grain refining and effect of the refiner's additions. Several factors include the fading effect of grain refinement and modifiers, inhomogeneous dendritic structure and non-uniform eutectic modification. In this study, standard ALCAN test was used by considering Taguchi's experimental design techniques to evaluate grain refinement and modification efficiency. The effects of five casting parameters on the grain size have been investigated for A357 casting alloy. The results showed that the addition of the grain refiner was the most effective factor on the grain size. It was found that holding time, casting temperature, alloy type and modification with Sr were less effective over grain refinement.

Effect of Al5Ti1B Grain Refiner and Al10Sr Modifier on Mechanical Properties and Corrosion Behavior of A360 Alloy

“…This has a positive effect on the mechanical properties of the alloy [19,20]. Also, grain refinement is known to be effective in increasing the fatigue resistance of aluminum alloys by reducing porosity and shrinkage [21,22]. Another master alloy modifier used to increase the machinability performance of cast aluminum alloys, not just the mechanical properties [23,24].…”

Archives of Metallurgy and Materials

“…The grain refinement and eutectic Si modification are widely used to improve their microstructure and mechanical properties of al-Si cast alloys [1][2][3][4][5][6]. normally, the addition of conventional master alloy such as the al-Ti, al-Ti-B or al-B and combinations between grain refiner and modifier alloy system such as al-Ti-B-Sr, al-Ti-C-Sr and al-B-Sr [7][8][9][10][11][12][13][14][15][16]. These combined master alloys allow for easier control of chemical composition compared to conventional additions.…”