Best conditions obtained for x1 336 x2 15 and x3 222

  • No School
  • AA 1
  • 35

This preview shows page 23 - 25 out of 35 pages.

studied for an OIH coating. Best conditions obtained for X1 = 3.36, X2 = 1.5, and X3 = 222 Ŷ C 244 2012 GPTMS, MTES Results revealed that the surface conditioning process was a key step to achieve the required anticorrosion properties of the substrate coated with the OIH 245 2013 GPTMS, Al(O s Bu) 3 OIH coating showed lower thickness in some points offering inferior protection against corrosive species 246 DGEBA, APTES, APTMS, GPTMS, TMSPh OIH coatings proposed showed high corrosion resistance with considerable improvements obtained by the OIHs based on APTMS and APTES 247 J. Coat. Technol. Res.
Image of page 23
thickness of the film and the deposition parameters. Latella et al. 256 synthesized and assessed the adhesion behavior and mechanical properties of OIH coatings. It was confirmed that the presence of a thermally grown oxide layer on the substrate, prior to the OIH sol–gel deposition, had an important role on the adhesion behavior (quality) between the film and the substrate. They also showed that the relation between the structure of the film and the mechanical properties of the coatings were influenced by the nature/character- istics of the organic substituent. Mammeri et al. 39 investigated and analyzed the mechanical properties of OIH gels reported by several authors and concluded that those properties were dependent on their micro- and nanostructures as well as the nature and extent of the organic–inorganic interfaces within the gel matrix. Some authors showed that when the substrate was subjected to localized plastic deformation due to impact with objects, or extensive plastic deformation due to substrate bending, cracks, and delamination developed easily in the thin films. 3 , 55 Others showed that electrodeposition (EPD) techniques provided fairly thick crack-free sol–gel-derived coatings when compared either to dip or spin coating techniques. 64 , 195 Castro et al. 257 combined the sol–gel method and the EPD process to prepare thick coatings onto metallic substrates obtaining crack-free deposits up to 20 l m in thickness after drying and crack-free glass-like coatings of 12 l m in thickness after sintering at 500 Ŷ C for 30 min. 257 The characterization of OIH materials by potentiodynamic methods showed that they have good performance against corrosion. Most of the studies reported in the literature were on planar samples and the films were deposited by dip or spin coating processes. Objects with complex shapes are far more challenging to coat using these methods, particularly if a uniform thickness is a strict requirement. For these reasons, additional coating methods besides spraying, dipping, spinning, and EPD are expected to be extensively tested and developed in the near future. 3 The deposition method selected might be a limiting variable as in certain circumstances it could negatively influence the performance of the OIH coating applied on the substrate. If the deposition method chosen is not the correct one, even with an OIH material displaying excellent barrier properties, the coating performance is compromised. The available deposition methods do
Image of page 24
Image of page 25

You've reached the end of your free preview.

Want to read all 35 pages?

  • Fall '19
  • 1984, oIh, OIH coatings

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern

Ask Expert Tutors You can ask You can ask ( soon) You can ask (will expire )
Answers in as fast as 15 minutes