Experimental modeling of phase transformations in a weakly ordered carbon substance under impact treatment
V.V. Ulyashev, T.G. Shumilova, B.A. Kulnitskiy, S.I. Isaenko, V.D. Blank
The results of experimental modeling of impact transformation of weakly ordered carbon substance by short-pulse laser radiation on glassy carbon are presented. The experiments yielded extremely high temperatures of ~14500 K and pressures of ~300 GPa, which are comparable with temperatures and pressure of the formation of large Earth’s meteorite craters. The analysis of the transformation products of a target substance showed melting of glassy carbon, its further solidifcation, partial crystallization upon cooling and formation of polyphase composites, which contain hexagonal nanocrystalline graphite and hollow onion-like and one- and two-layer fullerene-like structures. The synthetic products, including high-pressure carbon polymers and hollow onionlike multi-layer fullerene-like structures are of interest as carbon materials, which form at ultrahigh pressures and temperatures. The results of experimental modeling can also be used for the comparison with natural products to explain the formation of natural high-pressure carbon composites after non-graphite precursor.
Figures 7. Tables 1. References 64.
Key words: impact metamorphism, short-pulse laser exposure, transformation, carbon melting, glassy carbon, graphitization, high-resolution transmission electron microscopy, Raman spectroscopy
MINERALOGY № 3 2020