The Effect of Temperature on Synthetic Nano β-Eucryptite and Alumina Ceramic Materials: Thermal Expansion, Mechanical, and Physical Properties

Abstract

The capability to fabricate ultra-low and customizable CTE materials with good mechanical properties in a simple method was demonstrated in this work. For this purpose, nano beta-eucryptite and alumina powders were synthesized and used in the composite's fabrication. Four composites of alumina and a second-phase beta-eucryptite were prepared, containing 10, 20, 30, and 40 wt.% beta-eucryptite. The temperature effect on prepared composites is investigated. The results of XRD analysis and the microstructures of prepared composites are discussed with results of mechanical strength and thermal expansion at temperature ranges of 1400, 1500, and 1550 °C. The CTE of alumina-beta-eucryptite composites decrease as the beta-eucryptite content increases, reaching -1.036 × 10–6 °C−1. The findings show that a composite with a very low thermal expansion coefficient and good mechanical properties can be designed and used in different applications.

Design of alumina/β-eucryptite composite from alum sludge waste: physical properties, phase composition and coefficient of thermal expansion

“…The CTE of alumina/β-eucryptite composites reduces as the βeucryptite content increases, as shown in Table 1, which is a feature of β-eucryptite behavior [67][68][69][70]. As is common knowledge, β-eucryptite has a thermal expansion coefficient of -6.2x 10 -6 ºC -1 , whereas alumina has a thermal expansion coefficient of 10.3x 10 -6 ºC -1 [71,72]. The present of few amounts of spodumene does not effect on the trend of thermal expansion especially for sample contain 40 Wt.% of β-eucryptite, although thermal expansion of spodumene is about 0.9x10 -6 C −1 [73].…”