DI-UMONS : Dépôt institutionnel de l’université de Mons

Recherche transversale
(titres de publication, de périodique et noms de colloque inclus)
2019-12-13 - Colloque/Présentation - poster - Anglais - 1 page(s)

Dupla Florian , Renoirt Marie-Sophie , Gonon Maurice , Smagin Nikolay, Duquennoy Marc, Martic Grégory, Erauw Jean-Pierre, "Development of a high temperature pressure sensor to monitor the drying process of refractory concretes" in 2019 Annual Meeting of the Belgian Ceramic Society, Gand, Belgique, 2019

  • Codes CREF : Sciences de l'ingénieur (DI2000)
  • Unités de recherche UMONS : Science des Matériaux (F502)
  • Instituts UMONS : Institut de Recherche en Science et Ingénierie des Matériaux (Matériaux)

Abstract(s) :

(Anglais) During the drying of a refractory concrete structure, the liquid to vapor transition of the residual water may induce a high internal pressure. This may lead to the damaging and possibly the explosion of the concrete. To monitor the heating and control the pressure, a sensor based on the surface acoustic wave (SAW) technology is developed. SAW devices are widely used in different fields, such as filters, sensors and actuators. They can withstand harsh environments and be used as temperature, pressure, or humidity sensors. However, most of the SAW sensors are based on ferroelectric materials that cannot work at temperatures higher than 300°C. Some non-ferroelectric single crystals operate up to 1000°C but are very expensive [1]. Fresnoite based glass-ceramics are piezoelectric and non-ferroelectric polycrystalline materials, making it a good candidate for high temperature substrate [2][3]. These glass-ceramics are macroscopically piezoelectric through the preferentially oriented crystallization of the fresnoite crystals from the parent glass. The piezoelectricity of these glass-ceramics is consequently intrinsic to the microstructure. Then, conversely to ferroelectrics, they are not subject to depoling with temperature and over time, making them very useful for high temperature applications [4]. The fresnoite glass-ceramic used in this work contains 70 vol% of piezoelectric Sr2TiSi2O8 crystals and 30 vol% of residual glass. It is obtained by isothermal crystallization at 900°C of a parent glass of composition 2 SrO • TiO2 • 3.3 SiO2 • 0.2 K2O • 0.1 Al2O3. To generate and receive the SAW, two interdigital transducers (IDT) are realized by sputtering and laser ablation. The ability of the obtained device to generate and propagate SAW up to 950°C is demonstrated. The behavior of the SAW over temperature is strongly related to the mechanical properties of the glass-ceramic observed through impulse excitation technique (IET), and especially those of the residual glass. The prototype of a pressure sensor is proposed. It is realized by high temperature bonding of a thin fresnoite glass-ceramic plate (1 mm thick) on a thicker block having a hemispherical cavity.