Microstructure and properties of hot pressed Zr2(Al(Si))4C5/SiC composites

Hot pressed Zr-2(Al(Si))(4)C-5/SiC composites containing 0-30vol.% silicon carbide (SiC) particles have been investigated to determine the effect of composition (i.e. amount of SiC particles) on the microstructure, mechanical properties, and thermal properties. With increasing SiC volume contents, the Vickers' hardness, flexural strength, and fracture toughness of the composites were improved. Vickers' hardness. flexural strength, and fracture toughness increased from 12.2 GPa, 420 MPa and 4.64 MPa m(1/2) for monolithic Zr-2(Al(Si))(4)C-5 to 15.4 GPa, 592 MPa and 5.67 MPa m(1/2) for Zr-2(Al(Si))(4)C-5-30vol.% Sic, respectively. Specific heat capacity increased with Sic addition, while thermal conductivity decreased obviously with increasing SiC volume contents. The results here pointed to a potential method for improving strength and toughness of Zr-Al-C based ceramic composites. (C) 2009 Elsevier B.V. All rights reserved.