Sc<sub>1.5</sub>Al<sub>0.5</sub>W<sub>3</sub>O<sub>12</sub> Exhibits Zero Thermal Expansion between 4 and 1400 K
Junnan Liu, Helen E. Maynard‐Casely, Helen E. A. Brand, Neeraj Sharma
Abstract
Zero thermal expansion (ZTE) is a rare physical property; however, if accessible, these ZTE or near ZTE materials can be widely applied in electronic devices and aerospace engineering in addition to being of significant fundamental interest. ZTE materials illustrate this property over a certain temperature range. Here, orthorhombic (Pnca space group) Sc1.5Al0.5W3O12 is demonstrated to deliver ZTE over the widest temperature reported to date, from 4 to 1400 K, with a coefficient of thermal expansion of αv = −6(14) × 10–8 K–1. Sc1.5Al0.5W3O12 maybe is one of the most thermally stable materials known based on the temperature range of stability and the consistent thermal expansion coefficients observed along the crystallographic axes and volumetrically. Furthermore, this work demonstrates the atomic perturbations that lead to ZTE and how varying the Sc:Al ratio can alter the coefficient of thermal expansion.