{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

PTFEcompsys2008 - J Computer-Aided Mater Des DOI...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
J Computer-Aided Mater Des DOI 10.1007/s10820-007-9087-4 Effect of simulation conditions on friction in polytetrafluoroethylene (PTFE) Peter R. Barry · Inkook Jang · Scott S. Perry · W. Gregory Sawyer · Susan B. Sinnott · Simon R. Phillpot Received: 6 March 2007 / Accepted: 30 March 2007 © Springer Science+Business Media B.V. 2008 Abstract We report the results of molecular-dynamics simulations of friction at polyte- trafluoroethylene (PTFE) interfaces and show that the calculated tribological properties are robust against significant changes in the sliding speed and the morphology of the polymer. Keywords Tribology · Simulation · Molecular dynamics · Polymer 1 Introduction The terrestrial environment, in which surfaces are usually coated with physisorbed water and organic and inorganic molecules, is a very different tribological environment from the vacuum of space, which is dominated by clean, dry surfaces. As a result, the tribological behaviors of materials in space and on earth are significantly different from one another. This makes it particularly challenging to develop tribological coatings that work equally well in terrestrial and space environments. Multifunctional materials are being explored for use in such coatings; nanostructured polymer composites have been shown to be particularly good candidates, especially those that include polytetrafluoroethylene (PTFE) [ 1 3 ]. The C-F bond in PTFE provides both thermal and oxidative stability, and confers resistance to almost all solvents [ 4 ]. However, PTFE is known to have poor wear resistance, a problem that can be ameliorated by incorporation with nanoscopic fillers of a low wear material. For example, P. R. Barry · I. Jang · S. S. Perry · W. G. Sawyer · S. B. Sinnott · S. R. Phillpot ( B ) Department of Material Science and Engineering, University of Florida, Gainesville, FL 32611, USA e-mail: [email protected] W. G. Sawyer Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL 32611, USA Present Address: I. Jang Samsung Electronics Co., LTD, San #16 Banwol-dong, Hwasung-City 445-701, Gyeonggi-Do, Korea 123
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
P. R. Barry et al. ri g id movin g fixed thermostat normal (active) normal (active) thermostat 4.5 nm 0.6 nm 0.6 nm 1.2 nm 1.2 nm 2.2 nm 2.2 nm 1.0 nm Fig. 1 Schematic of the simulation set up. Both the top and bottom slabs of PTFE consist of three layers: the outer layers are held rigid with the relative atom positions fixed; the atoms in the thermostat layers are maintained at a temperature of 300 K. The atoms in the normal (active) regions evolve over the course of the simulations without any external constraints Sawyer et al. have created a nanocomposite of PTFE with alumina that has a reduction in wear rate of over two orders of magnitude compared with unfilled PTFE [ 5 ]. Molecular-dynamics (MD) simulations provide an ideal tool for identifying and charac- terizing the microscopic processes associated with low-friction behavior in PTFE materials.
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

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