Experimental and numerical analysis of the Macrosegregation in Al-Sn Alloys Directionally Solidified

Abstract

Mathematical modeling of the solute segregation has received special attention in the last decades. This segregation occurs due to the solute redistribution produced during the solidification process. The solute segregation can produce a compositional difference in the macroscopic scale, which is called macrosegregation. During the dendritic solidification, the macrosegregation is originated in the mushy zone and it is the consequence of the flow of the interdendritic liquid. The heterogeneity caused by the solute macrosegregation cause a negative effect on the mechanical properties such as tribological properties of the Al-Sn alloy systems. The main characteristic of the Al-Sn alloys is the low solid solubility of the Sn in the Al matrix favoring the marked macrosegregation. However, there is a lack of study about the macrosegregation in Al-Sn alloys. In this project of research, it is desired to develop a mathematical modeling to simulate the macrosegregation mechanisms in the Al-Sn alloys. This model is going to be based on the macroscopic equations of the mass conservation, quantity of movement, energy and chemical species, which will be solved by numerical methods. Simultaneously to the numerical analysis, directional solidification experiments of Al-Sn alloys will be performed to produce ingots and to obtain the macrosegregation profile. Experimental results will be compared to the results obtained by the mathematical model proposed and this model will be valued.