Abstract
When silica fibres are aged in severe conditions, their mechanical resistance is lowered and their lifetime is shortened.
However, the influence of water is more complex than assumed; work has been carried on for better understanding of
involved phenomena. Single-mode fibres were aged in hot water at 65 and 85°C for different aging durations. In a first step,
fibres were tested after successive 3 months periods, up to 27 months. A second series of experiments was implemented
on a shorter time scale, from one day to 3 months. Lifetime evolution of fibres subjected to static stress revealed an
oscillatory evolution, while fibre strength in the dynamic mode decrease. These observations have led to further
experiments, in which series of fibres were aged in hot water for a few days and subsequently put under static stress and
finally characterized. Tensile dynamic testing does not exemplify an anomalous behaviour. Similar results were observed
for fibres aged in water under a limited permanent stress. The current study has revealed that failure mechanism of aged
fibres involves surface phenomena, in relation to water activity. It is anticipated that the relaxation phenomenon control
could also lead to the fibre strength increase when subjected to dynamic fatigue.
Keywords
Silica optical fibres, Failure mechanisms, Static and dynamic fatigue testing, Structural relaxation.
Citation
I. SEVERIN, C. BORDA, M. POULAIN, R. EL ABDI, Failure mechanisms of silica optical fibre, Optoelectronics and Advanced Materials - Rapid Communications, 3, 7, July 2009, pp.659-663 (2009).
Submitted at: March 28, 2009
Accepted at: July 20, 2009