|About this Abstract
|Materials Science & Technology 2020
|Phase Transformations in Additively Manufactured Materials
|Rapid Solidification of Aluminium 6061 Using Fast Scanning DSC
|Lakshmi Ravi Narayan, Cain Hung, Rainer Hebert
|On-Site Speaker (Planned)
|Lakshmi Ravi Narayan
In order to model and predict solidification cracking during additive manufacturing, the fraction of solid must be known during rapid solidification as well as the microstructure formation. Fast-scanning Differential Scanning Calorimetry (DSC) was used in this study to determine the fraction of solid of aluminum alloy AA6061 during rapid solidification as a function of temperature and at cooling rates up to 40,000 Ks-1. The experimentally determined solid fractions were compared with analytical predictions. Microstructural analysis was performed on samples of these alloys after solidification at different cooling rates. The liquidus and solidus temperatures decrease by nearly 20 K and 300 K, respectively at the highest cooling rates over near-equilibrium freezing while the microstructure reveals a significant grain refinement. The changes in solidification and in microstructural behavior during rapid cooling are interpreted based on existing theories for their impact on solidification cracking.