2023 ASEE Annual Conference & Exposition

Abstract
Grain refinement is a technique applied widely in the manufacture of metal components to improve mechanical properties and understanding of the technique is valuable to those in a metal manufacturing industry and those that design metal components. As such, the development of grain structure in manufactured metal components is introduced to students of engineering technology in their first semester at xxxxxx University. To enhance course content understanding and improve learning efficiency, a lab-based group experiment that utilizes a materials-based grain refinement technique for aluminum castings was designed for use in a Materials and Processes course.
In this project, students performed a designed experiment by manufacturing two groups of tensile specimens using a sand casting process with pure molten aluminum and pure aluminum with the addition of a grain refiner and testing their hardness and tensile strength. The students are provided with a print of the casting with rigging and are required to demonstrate the ability to calculate the weight of grain refiner master alloy and pure aluminum to be mixed in the preparation of the melt, estimate the solidification time of the casting with Chvorinov's rule, and complete most aspects of the casting, specimen preparation, and property testing processes. The final deliverable of the experiment is a laboratory report of professional quality that includes statistical analysis of the mechanical properties. This paper compares the students’ grain structure related learning outcome achievements in respect to their previous exams as well as to the outcomes of previous students that completed a sand casting laboratory of a previous design.