Chemical Composition and Mechanical Characteristic of Nitrogen Ion Beam Mixed Carbon Nanolayer

Ion beam methods for modification of nanohardness of surface nanolayers of the titanium alloy Ti6AI4V were applied. After deposition of carbon nanolayers by electron beam evaporation, the ion implantation of nitrogen into samples was carried out. The chemical composition of the modified surface area was investigated by AES （auger electron spectroscopy）. The nanohardness of resulted ion beam modified surface nanolayers were investigated by nanoindentation testing. The measured concentration profiles indicate the atomic mixing of carbon into the substrate. It was found that the modified samples had a markedly higher nanohardness than the unmodified samples. The increased nanohardness is attributed to the newly created phases in the surface area.

Plasma-Induced Interfacial Processes in Metal Halides FTIR Gas Cell Windows

Fourier transform infrared spectroscopy(FTIR)is one of the most widely used vibrational diagnostic techniques to investigate gas-phase reactive oxygen and nitrogen species(RONS).However,the technique carries intrinsic challenges,particularly in relation to interfering peaks in the spectral data.This study explores the interfacial processes that occur when reactive oxygen and nitrogen species generated by a non-equilibrium air plasma interact with the metal halide windows of an FTIR gas cell,leading to the appearance and evolution of spurious absorption peaks which complicate spectral interpretation.Raman spectroscopy,X-ray photoelectron spectroscopy,time of flight secondary ion mass spectrometry and attenuated total reflectance-FTIR spectroscopy were used to elucidate the origin of spurious absorption peaks spanning the 1400-1300 cm^(-1)spectral range as a result of KBr exposure to plasma generated species.It was found that plasma exposed KBr contained a lower atomic fraction of Br which was replaced by the NO3nitrate group,the main absorbance peak of which progressively evolved with plasma exposure and affected the window transparency over the corresponding FTIR region.A correlation was revealed between KNO_(3)formation,plasma power and exposure time to a growth and change in molecular vibrational energies corresponding to asymmetric NO3stretching vibrations in the KNO_(3)structure.