Fibers 2019, 7(1), 7; https://doi.org/10.3390/fib7010007
Investigation of Chemical and Physical Surface Changes of Thermally Conditioned Glass Fibres
Peter G Jenkins 1,*
, Liu Yang 1, James L Thomason 1, Xinyong Chen 2, John F Watts 3 and Steven J Hinder 3
, Liu Yang 1, James L Thomason 1, Xinyong Chen 2, John F Watts 3 and Steven J Hinder 3
1
Department of Mechanical & Aerospace Engineering, University of Strathclyde, 75 Montrose Street, Glasgow G1 1XJ, UK
2
School of Pharmacy, University of Nottingham, University Park, Nottingham NG7 2RD, UK
3
The Surface Analysis Laboratory, Department of Mechanical Engineering Sciences, Mail Stop A1, University of Surrey, Guildford, Surrey GU2 7XH, UK
*
Author to whom correspondence should be addressed.
Received: 27 November 2018 / Revised: 27 December 2018 / Accepted: 8 January 2019 / Published: 15 January 2019
(This article belongs to the Special Issue Glass Fibers 2018)
Abstract
A number of analytical techniques were applied to investigate changes to the surface of unsized boron-free E-glass fibres after thermal conditioning at temperatures up to 700 °C. Novel systematic studies were carried out to investigate the fundamental strength loss from thermal conditioning. Surface chemical changes studied using X-ray photoelectron spectroscopy (XPS) showed a consistent increase in the surface concentration of calcium with increasing conditioning temperature, although this did not correlate well with a loss of fibre strength. Scanning electron microscopy fractography confirmed the difficulty of analysing failure-inducing flaws on individual fibre fracture surfaces. Analysis by atomic force microscopy (AFM) did not reveal any likely surface cracks or flaws of significant dimensions to cause failure: the observation of cracks before fibre fracture may not be possible when using this technique. Fibre surface roughness increased over the whole range of the conditioning temperatures investigated. Although surface roughness did not correlate precisely with fibre strength, there was a clear inverse relationship at temperatures exceeding 400 °C. The interpretation of the surface topography that formed between 400–700 °C produced evidence that the initial stage of phase separation by spinodal decomposition may have occurred at the fibre surface. View Full-TextKeywords:
glass fibre; heat treatment; strength loss; X-ray photoelectron spectroscopy (XPS); atomic force microscopy (AFM)
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Jenkins, P.G.; Yang, L.; Thomason, J.L.; Chen, X.; Watts, J.F.; Hinder, S.J. Investigation of Chemical and Physical Surface Changes of Thermally Conditioned Glass Fibres. Fibers 2019, 7, 7.
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