@Article{SouzaGoRiDiUeSc:2017:PhChEf,
               author = "Souza, Gelson B. and Gonsalves, Silvio H. and Ribeiro, Karen C. 
                         and Ditzel, Dair G. and Ueda, M{\'a}rio and Schreiner, Wido H.",
          affiliation = "{Universidade Estadual de Ponta Grossa (UEPG)} and {Universidade 
                         Estadual de Ponta Grossa (UEPG)} and {Universidade Estadual de 
                         Ponta Grossa (UEPG)} and {Universidade Estadual de Ponta Grossa 
                         (UEPG)} and {Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         {Universidade Federal do Paran{\'a} (UFPR)}",
                title = "Physical and chemical effects of the hydrogen irradiation on 
                         nitrided titanium surfaces",
              journal = "Surface and Coatings Technology",
                 year = "2017",
               volume = "312",
                pages = "91--100",
                month = "Feb.",
             keywords = "Denitriding, Hydrogen, Plasma immersion ion implantation, Plasma 
                         nitriding, Titanium.",
             abstract = "Many applications aiming the use of titanium and titanium-based 
                         materials involve the surface interaction with protons or hydrogen 
                         isotopes, such as in chemical and nuclear power plants, marine and 
                         aerospace environments. Because of the high affinity of titanium 
                         for hydrogen and the consequent deleterious effects, the study of 
                         surface interactions contributes to the understanding of the 
                         protection mechanisms, such as the H-diffusion barrier provided by 
                         nitriding, as well as the fine surface tailoring achieved by 
                         hydrogenation. Nitrided titanium surfaces were produced via plasma 
                         nitriding (PN), carried out at 400 °C and 600 °C. Afterwards, 
                         titanium and nitrided titanium were submitted to the hydrogen 
                         plasma immersion ion implantation (H-PIII), using ion energies 
                         from 1.2 to 5.0 keV. The hydrogen modifications imposed were 
                         restricted to the nanometer depth range, causing no significant 
                         variations in hardness and elastic modulus (measured in depths 
                         larger than 70 nm) or in the crystalline structure, as inferred 
                         from nanoindentantion and grazing incidence X-ray diffraction, 
                         respectively. From the X-ray photoelectron and micro-Raman 
                         spectroscopies, the hydrogen irradiation was found to cause 
                         denitriding on the nitrided titanium, changing the TiN 
                         stoichiometry as a consequence of conjoined physical and chemical 
                         effects on the surface atoms. The atomic N/Ti ratio changed from 
                         0.9 (not hydrogenated) to 0.6 (5 keV) up to ~ 2 nm depth. The Ti/N 
                         decrement and the resulting TiO2 surface layer growth followed 
                         approximately linear correlations with the implantation energies. 
                         Additional investigations with Fourier-transform infrared 
                         spectroscopy disclosed vibrational bands featured by a strong line 
                         at 668 cm\− 1 (possibly OTi(OH)2) in samples submitted 
                         independently to PN and H-PIII, suggesting that different 
                         mechanisms of hydroxyl absorption on titanium took place on those 
                         surfaces.",
                  doi = "10.1016/j.surfcoat.2016.10.005",
                  url = "http://dx.doi.org/10.1016/j.surfcoat.2016.10.005",
                 issn = "0257-8972",
             language = "en",
           targetfile = "souza_physical.pdf",
        urlaccessdate = "30 abr. 2024"
}