Influence of the addition of Cr2O3 and SiO2 on the tribological performance of alumina ceramics

Abstract

Although ceramic materials are widely selected in the design of components for high engineering applications, the manufacture of ceramic components is quite different to that of metallic or polymer materials. The original material, the type of the sinter additive and sinter conditions, can modify the mechanical, chemical and tribological properties of a ceramic component. For instance, in hot press process of alumina ceramic, additional compounds are added to decrease the sintering temperature of the material, which means a decrease in manufacturing time and cost. In this investigation we studied and explored the influence of additional compounds, load and test speed values on the friction and wear performance of alumina ceramic. Wear tests using a pin-on-disc machine were carried out for pure alumina and alumina samples contained 3 wt.% SiO2 and 1.5 wt.% Cr2O3 addition compounds. Test conditions covered 0.5 and 1 m/s speeds and 2.5, 5 and 10 N loads. The specific wear rates were deduced from mass loss. The wear rate for pure alumina was between 8 X 10(-8) and 8 X 10(-7) mm(2)/N, while the wear rate values for alumina with Cr2O3 + SiO2 were in the order of 10(-6) mm(2)/N. Moreover, the wear rate showed more sensitivity to the applied load, particularly at low sliding speeds. (C) 2003 Elsevier Science B.V. All rights reserved.