Influence of ageing conditions on the mechanical properties of Te–As–Se fibres

Abstract

Mechanical properties of chalcogenide glass fibres from the system Te–As–Se have been investigated as a function of environment (ageing in air, under vacuum and under static stress) through a series of tensile strength measurements. It is shown that the surface quality has a decisive effect on the tensile strength of the fibre. Surface degradation due to air oxidation induces a noticeable decrease in strength. However, a series of mechanical tests performed on fibres preserved in vacuum indicate that structural relaxation of the chalcogenide glass also plays a preponderant role in the loss of mechanical strength. Indeed the trend in mechanical properties correlates well with calorimetric characterizations performed on these glasses. Finally, it is observed that the application of a long-term static stress along the fibre induces a net increase in the tensile strength. These effects are associated with a partial alignment of the chalcogenide chains present in the glass structure. This is consistent with the observation of a longitudinal permanent deformation of these fibres under static stress.

Photoinduced fluidity in chalcogenide glasses at low and high intensities: A model accounting for photon efficiency

“…2 clearly show that light has no effect on TAS fibers. This is because most of the light is absorbed near the surface and produces only surface effects: 29 the light used has a very low penetration in TAS glass because it corresponds to energies far higher than the Tauc energy of this glass. It is important to note that temperature measurements, with an infrared thermography camera ͑Thermacam FLIR Systems͒ with a sensitivity of 2°C, showed no warming due to absorption susceptible to enhance the fluidity.…”

Structural characterizations of As–Se–Te glasses

“…This extension of the transmission window in the farinfrared spectral domain suggest the use of As-Se-Te rather than As-Se glasses for the development of optical fiber sensors [4][5][6].…”

Aging in chalcohalide glasses: Origin and consequences

“…The tensile strength of chalcogenide glasses has been reported to decrease over prolonged storage at room temperature in both vacuum and air atmosphere [9][10][11][12]. Therefore, the strength degradation has been claimed to primarily be a consequence of the physical aging process [9].…”

“…Therefore, the strength degradation has been claimed to primarily be a consequence of the physical aging process [9]. However, a recent study has shown that the strength degradation occurs faster in air than in vacuum [12], indicating the importance of chemical aging. Furthermore, the structural origin of the physical aging remains unclear [13][14][15][16], and the reaction mechanism during chemical aging has not been well understood [12].…”

“…However, a recent study has shown that the strength degradation occurs faster in air than in vacuum [12], indicating the importance of chemical aging. Furthermore, the structural origin of the physical aging remains unclear [13][14][15][16], and the reaction mechanism during chemical aging has not been well understood [12]. In this Letter, we identify the chemical evolvement during the chemical aging in chalcohalide glasses and find out how both physical and chemical aging affect a mechanical property such as hardness.…”