Effect of the Composition and Structure of Silicon Carbide Composites on Wear Mechanisms

 
A.G.Dovgal,
 
A.Panasyuk,
  

I. M. Frantsevich Institute for Problems of Materials Science of the NAS of Ukraine, Krzhizhanovsky str., 3, Kyiv, 03142, Ukraine
Powder Metallurgy - Kiev: Frantsevich Institute for Problems of Materials Science NASU, 2012, #07/08
http://www.materials.kiev.ua/article/1062

Abstract

The tribotechnical characteristics of SiC–Al2O3 and SiC–Al2O3–ZrO2 ceramic composites are studied during plane-on-plane friction without lubrication in a wide range of speeds (2–7 m/sec) and loadings (1–7 MPa). This testing pattern allows modeling the performance of composites as sealing elements for centrifugal pumps. The influence of 20, 50, and 80 wt.% aluminum oxide in silicon carbide on the wear rate and mechanisms is analyzed. It is shown that higher alumina content of the SiC–Al2O3 ceramics changes the wear regularities: oxidative–adhesive wear takes place for materials containing 20 wt.% Al2O3 and mechanochemical wear for SiC–80 wt.% Al2O3. The tribotechnical characteristics of SiC–Al2O3–ZrO2 (SIAL-Z) ceramics have been studied. The ratio of aluminum and zirconium oxides in this material is eutectic, which substantially decreases the hot pressing temperature and promotes a fine-grained structure. Oxidative wear takes place during friction of the SIAL-Z ceramics against a steel counterface. This composite has the highest tribotechnical characteristics among the materials of interest.


CERAMIC MATERIAL, END-FACE COMPACTION, SILICON CARBIDE, WEAR MECHANISM, WEAR RESISTANCE