Optimization and Utilization of Semisolid Casting Process for Semisolid Welding of Al-6061 Alloy

Semisolid processing is one of the modern routes in sound and near net shape parts production. Preparation of semisolid slurry using a cooling slope is increasingly becoming popular, primarily because of its simplicity in design and ease of control of the process. In this research, the microstructures of Al6061 semisolid alloy cast via a miniature cooling slope were investigated. The properties of final microstructures such as sphericity depend on such casting factors as pouring rate, superheat, slope angle and slope length. In this work, the relationships between the process parameters and microstructural properties of semisolid castings were identified using a two level factorial design. The results showed that simultaneous increase or decrease in pouring rate and cooling slope length can result in the most proper microstructure. The optimum result was then successfully used for semisolid welding of the alloy.