TRIBOLOGICAL BEHAVIOR OF LIQUID PHASE SINTERED SiC CERAMICS UNDER DRY CONDITION

Abstract

Silicon carbide (SiC) ceramics with aluminum oxide (Al2O3)/aluminum nitride (AlN) and yttrium(III) oxide (Y2O3) as sintering aids are hot-pressed. The microstructure and tribological behavior of the as-prepared SiC ceramics slide against tungsten carbide (WC, Co bonded) and Al2O3 under variable velocities, loads, and temperatures are studied. The results showed that by using Al2O3–Y2O3 as a sintering aid, a fully dense (98 %) SiC ceramic is obtained at 1950 °С and 13 MPa. The sample coupled with WC, the friction coefficient (CoF) of the SiC ceramic is observed low at the applied high load, velocity, and temperature. On the other hand, in the sample coupled with Al2O3, the CoFs of the SiC ceramics are found low at the applied high load, moderate velocity, and low temperature. Coupled with the two tribo-pairs, the wear rates (WRs) of the SiC ceramics are not sensitive to the change in load, while CoF and WR of SiC ceramic increase with velocity initially, and then decrease. At the 0.05 m/s and 1.0 m/s, the WRs of both tribo-pairs are as low as 10–5 mm3/(Nm). The reduction in CoFs and WRs is strongly related to the formation of tribo-layers. The full article will be published in the translated version of the journal Glass and Ceramics, 2022, V. 79, No. 3–4