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DOE OSTI · 1777772

Surface and subsurface characterization of laser-interference structured Ti6Al4V

Abstract

Ti6Al4V specimens were exposed to high-energy laser pulses of 1.24 J/cm 2 fluences per pulse using a two-beam optical configuration to attain laser-interference. In addition to the formation of periodic surface textures by laser-interference, scanning electron microscope (SEM) images demonstrated several microstructural changes on the surface processed. Moreover, the surface and subsurface of Ti6Al4V specimens were characterized for the as-received and laser-interference processed conditions using x-ray photoelectron spectroscopy (XPS) and electron energy dispersive spectroscopy (EDS). The XPS data showed that this laser technique is effective at removal of surface contaminants for Ti6Al4V. The XPS analysis also revealed the formation of an oxy-nitride layer on the laser treated material. Finally, the microstructure analysis indicates that grain refinement, dendrite and twin structures were found near the surface due to laser processing.

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Chen, Jian, Sabau, Adrian, Meyer III, Harry, Leonard, Donovan. 2021-03-19. Surface and subsurface characterization of laser-interference structured Ti6Al4V. https://doi.org/10.1016/j.apsusc.2021.149576

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36 MATERIALS SCIENCE↗