author = "Oliveira, Rog{\'e}rio de Moraes and Hoshida, Lilian and Oliveira, 
                         Aline C. and Silva, Matheus Moraes Novaes Ferreira da and Pichon, 
                         Luc and Santos, Nazir Monteiro dos",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Universidade Federal 
                         de S{\~a}o Paulo (UNIFESP)} and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {CNRS-Universit{\'e} de Poitiers-ENSMA} and 
                         {Instituto Nacional de Pesquisas Espaciais (INPE)}",
                title = "Evaluation of the resistance to oxidation of niobium treated by 
                         high temperature nitrogen Plasma Based Ion Implantation",
              journal = "Surface and Coatings Technology",
                 year = "2017",
               volume = "312",
                pages = "110--116",
                month = "Feb.",
             keywords = "High temperature, Ion implantation, Niobium, Oxidation, Plasma.",
             abstract = "Niobium is a technological material used in very distinct 
                         applications. Most of them as an alloying element, making part of 
                         superconducting radio frequency cavities, nuclear reactor 
                         components, missiles, rockets, aviation and space-system 
                         engineering. Nevertheless, although refractory, pure niobium 
                         presents as the main drawback the poor oxidation resistance in 
                         moderate and high temperatures. Different treatment methods have 
                         been used to mitigate this issue, as is the case of cementation, 
                         conventional nitridation, CVD and PVD processes. The evaluation of 
                         the resistance to oxidation of Nb treated by high temperature 
                         nitrogen plasma based ion implantation (HTPBII) has been described 
                         herein. The implanted nitrogen in this case easily diffuses to 
                         inner layers of niobium heated up to 1250 C during treatment, 
                         reaching depths of about 7 \μm, while its atomic 
                         concentration of about 25% remains stable for almost the whole 
                         treated surface. This allows the formation of thick nitride 
                         layers. The produced interstitial nitrides have outstanding 
                         properties as the high hardness and strength, like ceramics, and 
                         high thermal and electrical conductivities, like metals. In 
                         addition, these refractory nitrides also present good chemical 
                         resistance and superior resistance against oxidation. The 
                         investigation performed herein includes a series of 
                         characterization performed by X-ray diffraction (XRD), X-ray 
                         photoelectron spectroscopy (XPS), glow discharge optical emission 
                         spectroscopy (GDOES), scanning electron microscopy (SEM), and 
                         thermogravimetric analysis (TGA). The oxidation of the 
                         ion-implanted niobium was retarded in comparison with the 
                         untreated counterpart in about 130 C. Isothermal analysis 
                         revealed reduced oxidation rate when treatment time was extended 
                         from 4 h to 8 h.",
                  doi = "10.1016/j.surfcoat.2016.10.012",
                  url = "http://dx.doi.org/10.1016/j.surfcoat.2016.10.012",
                 issn = "0257-8972",
             language = "en",
           targetfile = "oliveira_evulation.pdf",
        urlaccessdate = "29 nov. 2020"