Tribological Characteristics Manufactures SiC by Liquid Phase Sintered Method

Abstract

SiC materials have excellent high temperature strength, low coefficient of thermal expansion, good resistance to oxidation and good thermal and chemical stability etc. In this study, monolithic liquid phase sintered SiC (LPS-SiC) was made by hot pressing method with nano-SiC powder an average particle size is 30nm and less. Alumina (Al2O3), yttria (Y2O3) and silica (SiO2) particles were used for sintering additives. To investigate effects of SiO2, Al2O3/Y2O3 composition was fixed and then ratios of SiO2 were changed as seven kinds. Materials have been sintered for 1 hour at 1760, 1780 and 1800 under the pressure of 20MPa. The system of sintering additives which affects a property of sintering as well as the influence depending on compositions of sintering additives were investigated by measurement of density, mechanical properties such as Vickers hardness and sliding wear resistance were investigated to make sure of the optimum condition which is about matrix of SiCf/SiC composites. The abrasion test condition applies to load of 20N at 100rpm for 20min. Sintered density, abrasion property of fabricated LPS-SiC increased with increasing the sintering temperature. In case of LPS-SiC with low SiO2 content, has very excellent wear resistance.