Physical Aging of Titanium/FM-5 Polyimide Adhesive Structural Laminates: Nanoindentation Measurement of the Interface Properties

  1. Dr. P. J. Winkler
  1. James D. Holbery1 and
  2. Robert M. Fisher2

Published Online: 23 DEC 2005

DOI: 10.1002/3527606025.ch39

Materials for Transportation Technology, Volume 1

Materials for Transportation Technology, Volume 1

How to Cite

Holbery, J. D. and Fisher, R. M. (2000) Physical Aging of Titanium/FM-5 Polyimide Adhesive Structural Laminates: Nanoindentation Measurement of the Interface Properties, in Materials for Transportation Technology, Volume 1 (ed P. J. Winkler), Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, FRG. doi: 10.1002/3527606025.ch39

Editor Information

  1. DaimlerChrysler AG, Forschung und Technologie, Postfach 800 465, 81663 München, Germany; Tel.: 089–607 22393; Fax: 089–607 28627

Author Information

  1. 1

    Centre Suisse d'Electronique et de Microtechnique SA, Neuchâtel, Switzerland

  2. 2

    Department of Materials Science and Engineering, University of Washington, Seattle, WA USA 98195

Publication History

  1. Published Online: 23 DEC 2005
  2. Published Print: 20 APR 2000

Book Series:

  1. EUROMAT 99

ISBN Information

Print ISBN: 9783527301249

Online ISBN: 9783527606023

SEARCH

Keywords:

  • transportation technology;
  • materials;
  • aerospace applications;
  • titanium/FM-5 polyimide adhesive structural laminates;
  • physical aging;
  • measurement of interface properties

Summary

In an effort to improve the bonding capabilities of titanium for high speed civilian airplanes, silicate/zirconate sol-gel and plasma sputtered chromium coated substrates have been adhered using a combined PETI-5 polyimide pseudo-thermoplastic primer/adhesive system. Composite laminates were exposed to thermal aging up to 2000 hours at 194°C and subsequently nanoindentation testing has been performed across the interface to determine material modulus and hardness deviations. Inhomogeneities at the interface and in the coating and primer thickness' (nominally 100 nm each) mandated that both a low load (as low as 25 µN) and a 90° Cube-corner diamond tip be used to obtain sub-micron resolution. Height profiles of the prepared interfaces indicate sol-gel interfaces to be more uniform than chromium likely due to the higher sol-gel hardness and the higher wear rate of chromium.

Indentation studies of sol-gel coated titanium substrates indicate a pronounced step-wise gradient across the interface with modulus values depending upon the loading level and corresponding indentation depth. Thermal aging produced an increase in both the PETI-5 primer and adhesive modulus by 15 % and upwards of 30 % respectively, while the sol-gel modulus increased by approximately 10 %, beginning at a nominal initial modulus of 46–54 GPa. Chromium behaved in a similar manner to the Sol-gel, with a nominal “As Manufactured” modulus between 24–26 GPa. An exposure level at 1000 hours showed a 20 % increase in the chromium modulus. An increase in plastic deformation resulting from the effect of aging has also been observed.