Fabrication of near-zero thermal expansion of fully dense β-eucryptite ceramics by microwave sintering

Microwave heating is proposed as the non-conventional technique for the sintering of optimal lithium aluminosilicate compositions of the β-eucryptite system. The coefficient of thermal expansion and mechanical properties of the sintered samples has been studied under the influence of microwave heating. The ad hoc synthesized β-eucryptite together with the microwave sintering technique developed in this work open the opportunity to produce breakthrough materials with low or negative coefficient of thermal expansion and excellent mechanical properties, as Young's modulus of 110 GPa. The combination of rapid heating with low energy applied by the microwave technology (eco-friendly process) and the dramatic reduction in cycle time allows densification without glass phase formation. Results of the coefficient of thermal expansion of the β-eucryptite ceramics presented here under cryogenic conditions will be of value, for example, in the future design of new composite materials for space applications. Copyright © 2013 Published by Elsevier Ltd and Techna Group S.r.l. All rights reserved.The authors would like to thank Dr. Emilio Rayón for performing the nanoindentation analysis in the Materials Technology institute (ITM) of the Polytechnic University of Valencia (UPV) and your financial support received of UPV under Projects SP20120621 and SP20120677 and Spanish Government through the Project MONIDIEL (TEC2008-04109). A. Borrell, acknowledges the Spanish Ministry of Science and Innovation for a Juan de la Cierva contract (JCI-2011-10498) and SCSIE of the University of Valencia.Peer Reviewe