Mechanical Engineering (B.S.)
Document Type and Release Option
Thesis (open access)
Dr. Mingzhi Xu
As grey iron casting accounts for a significant share of the foundry industry, proper understanding of the effects of solidification and growth mechanisms on the mechanical properties of grey iron is crucial. Prior experimentation has been performed examining early stage solidification and growth of the carbon phase of ductile iron, in which rapid quench samples are obtained which detail austenite-graphite interactions during solidification. This prior experimentation is built upon in though this research and applied to examine the early stage growth of flake graphite in grey iron. The purpose of this research is to validate a proposed fast-quench method by observing type A flake graphite development and producing cooling curves for both quenched and unquenched grey iron samples. It was found that proper inoculation can allow for type A flake graphite morphologies in the proposed thin section sample castings. Cooling curves were additionally obtained for both quenched and unquenched samples, however the rate of cooling was slower than predicted in simulation and samples were quenched directly from the liquid state rather than during solidification which allowed for analysis of type E graphite rather than the desired type A morphology. This research successfully set the stage for future work in developing more accurate cooling curve simulations and obtaining precise fast quench samples for metallography at various stages in the solidification and growth of grey iron.
Liggett, James C., "Examination of Early Stage Grey Iron Solidification through the Development of Fast-Quench Methodology" (2020). University Honors Program Theses. 539.