Conventional sintering of LAS–SiC nanocomposites with very low thermal expansion coefficient

Abstract

Very low thermal expansion materials have been developed in a wide temperature range from −150 °C to 450 °C. These very low expansion materials are composed of a lithium aluminosilicate matrix with dispersed silicon carbide nanoparticles. The nSiC content in the most stable composite has resulted to be 27 vol.%. Powder processing and sintering temperature control have been found to be of key importance in order to obtain low porosity sintered nanocomposites. Here it is proposed the sintering by pressureless methods (conventional sintering) in order to obtain a LAS–nSiC nanocomposite with improved mechanical properties and excellent expansion behaviour by means of control of the phase reactions and glass formation during sintering.