Characterization of vapour plume species and deposition residues resulting from pulsed laser ablation of a graphite/epoxy composite
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A modified time-of-flight mass spectrometer fitted with a special collection stage for carbon-coated transmission electron microscope specimen grids is used to monitor laser-pulse ablation products from graphite/epoxy composite targets. Scanning electron microscopy observations show ablation damage to consist of matrix pyrolysis, fibre fracture and spallation of fragments which include elemental hydrogen, carbon epoxide and acetylene groups. Transmission electron microscope examination of specimen grids showed a variety of crystals and polycrystalline hexagonal graphites having a wide range of shapes including spheres and faceted polyhedra and platelets, textured flake structures, and microrosettes. These observations lend some credibility to a model for laser-shock and pyrolysis effects which create molecular plume fragments and deposition fragments of hexagonal graphite.
KeywordsPyrolysis Transmission Electron Microscope Examination Transmission Electron Microscope Specimen Composite Target Acetylene Group
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