Semisolid metal processing parameters and metallurgical properties: An overview

The current article is to present a comprehensive summary of the most widely used semisolid metal (SSM) processing parameters with their concomitant metallurgical properties. The processing parameters include shear force (stress), shear rate, shear time, cooling rate, pouring temperature, holding temperature, holding time, and sample size, whereas the metallurgical properties comprise alloy composition, fraction solid, particle size and distribution. The fundamental theory and the effect of each parameter in characterising the flow behaviour and microstructure of the SSM slurry, together with several recent case studies, are given. Even though these parameters play a vital role in SSM rheological studies, not every parameter must be necessitated in a single SSM technique since different SSM operations require different operating parameters. It can be seen from this article that most of the process parameters do not exhibit linear development trends, which might induce adverse effects on the responding variables upon the application of the excessively low or high degree of given parameters. Thus, an ample comprehension of the rheological characteristics of semisolid metal slurries coupled with the appropriate combination of process parameters are the key elements to developing effective SSM technologies.