PSI - Issue 16

Barbara Nasiłowska et al. / Procedia Structural Integrity 16 (2019) 230 – 236

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Barbara Nasiłowska et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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the droplets. Such disturbance could influence the contact angle measurement. The scheme of designed measurement is presented in Fig. 3. Five different surfaces were produced to characterize their wettability: (a) glass, (b) glass with GO film, (c) steel S235, (d) steel S235 with GO film, (e) steel S235 with initiated surface corrosion. 2.4. FTIR analysis Chemical analysis of the samples was made with use of Fourier Transformed Infrared Spectroscopy, absorption reflectance technique. The technique combines absorption of the radiation in thin layer of the sample and reflection of the IR beam in all directions. The IR beam filter through analysed layer where is absorbed, scattered and radiated in every direction and directed to the detector. Fragments of the surfaces were examined at the contact points of acrylic resin with steel/glass. Histochemical maps were obtained during scanning the surface. Before analysis the samples were not subjected to any preparation process. FTIR analysis was conducted with use of Nicolet TM iN TM 10 microscope with MCT-A detector. Measurements were made in MIR range 400 – 4000 cm -1 with 64 scans for each sample and 4 cm -1 resolution.

3. Results

3.1. Structural characteristics The surface before wettability measurements was characterized with roughness parameters as: Rq – root mean squared, Rp – maximum peak height, Rv – maximum valley depth, Rz – average distance between the highest peak and lowest valley in each sampling length, Ra – arithmetical mean deviation of the assessed profile.

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Fig. 4. (a, c) glass surface morphology registered with confocal scanning microscope and SEM, (b, d) before and after GO deposition.

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Fig. 5. (a, b) steel sufrace morphology recorded with confocal scanning microscope (left column) and SEM (right column of, steel S235 before GO deposition, (c, d) after GO deposition and (e, f) with initiated surface corrosion.