Senior Design 2020 – Materials Science and Engineering Team 6
Materials Science and Engineering Team 6
Alex Coffey Justin Hewitt
Optimization of high-temperature rheometry for thixocasting applications
The main goal of this project is to optimize the viscosity measuring capabilities of Anton Paar’s FRS1800 above temperatures of 1300 °C. A titanium cobalt alloy was selected for the project because of the particular challenges to measure reactive metals and at high temperatures. The pronounced temperature range during which solid and liquid phases coexist additionally allows the study of viscosities of the liquid and solid state. This viscosity information is important for thixocasting. A suitable crucible and bob material had to be found in order for the liquid titanium alloy to be measured. Graphite with and without yttria coatings have been evaluated. Testing was applied at different shear rates to evaluate the way the alloy behaves under different conditions. This was done in the fully liquid state as well as the partially solidified state, below the liquidus. Using an oscillatory measurement, the complex moduli were evaluated in order to identify the elastic and viscous components of the sample.