|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||Role of Cyclic Solid-Solid Phase Transformations in Microstructure Evolution during Thermal Gyrations during Additive Manufacturing
||Ryan Dehoff, Niyanth Sridharan, Avinash Prabhu, Naren Raghavan, Michael Kirka, Anil Chaudhary,
|On-Site Speaker (Planned)
Performance of additively manufactured metallic components is related to microstructural heterogeneity brought about by liquid-solid and solid-state transformations that occur during repeated thermal cycling. In this talk, we will present typical thermal gyrations experienced by direct energy and powder bed additive manufacturing processes. The sensitivities of these gyrations with reference to processing parameters and beam scanning strategies are calculated using computational heat transfer models for Ti- and Ni-alloys. In the second step, the effect of these thermal cycles on interdendritic segregation and redistribution of solute will be discussed based on computational thermodynamic and kinetic models. Finally, the repeated nucleation, growth and dissolution of product phase within a parent phase will be described using simultaneous transformation kinetic modeling. Based on the above evaluations, hypothesis for obtaining homogeneous microstructure in additively manufactured components will be presented. Preliminary experimental results that support this notion for titanium and nickel alloys will be presented.
||Planned: A print-only volume