|About this Abstract
|2022 TMS Annual Meeting & Exhibition
|Phase Transformations and Microstructural Evolution
|O-22: Carbon Transformations in Rapidly Solidified Nickel-carbon Ribbon
|Gina Greenidge, Samuel Price, Jonah Erlebacher
|On-Site Speaker (Planned)
We report the microstructural evolution of rapidly solidified nickel-carbon alloys, as-formed via melt-spinning and after annealing. Via melt spinning, we attained metastable solid solubility of carbon in nickel. Subsequent high-temperature annealing led to the controlled precipitation of carbon from the nickel matrix onto the ribbon free surfaces as well as the growth of spherical precipitates within the bulk of the ribbon. Freestanding carbon was excavated from the alloy via chemical dissolution of the metal and characterized by electron microscopy and Raman spectroscopy. We determined that the microstructure of carbon could be tuned by varying the precursor carbon content from 4 – 12 at. % and annealing the precursor ribbon at temperatures ranging from 400 – 1200 ℃. Via the step-wise variation of these parameters, we sequentially transformed amorphous carbon nanospheres with a BET surface area of 203.4 m2/g into thick, highly crystalline flakes of graphite.
|Phase Transformations, Solidification, Other