The Abrasive Wear of Non-oxide Ceramics and Their Composites inDifferent Environments
Z. Pędzich1, G. Grabowski1, I. Saferna1, J. Szczerba1, M. Kot2,
1AGH - University of Science and Technology, Faculty of Materials Science and Ceramics, Department of Ceramics and Refractory Materials, Mickiewicza 30, 30059Kraków, Poland;
2AGH - University of Science and Technology, Faculty of Mechanical Engineering and Robotics, Department of Machine Design and Technology, Mickiewicza 30, 30059 Kraków, Poland;
e:
Silicon carbide and silicon nitride are recognized as phases with very good mechanical properties. Many parts of machines and mechanical devices are made of these materials. Composites basing on both mentioned phases have significant potential of properties improvement.
The aim of presented work was to check the influence of the selected second phase particles on the silicon carbide and silicon nitride wear in different conditions.
Two types of tests were performed:
- the type of Dry Sand Test based on the ASTM test [1], which indicates wear susceptibility of material for wear during abrasive action of hard particles without any lubricant. The test duration was 2000 rotation of the wheel.
- the Miller Test based on the ASTM test [2]. This test examine the wear of materials during action of hard particles in wet environment (pulp). The test duration was 6 hours. On its basis the SAR number values for all investigated materials were calculated.
In both tests the same abrasive powder was used – SiC 80 with the mean diameter of about 160-200 micrometers.
The detail microstructural and mechanical characterization of investigated materials was done. Residual stress state caused by coefficients of thermal expansion mismatch were calculated using FEM approach. The second phases for composites were selected to introduce the compressive stress state into the matrix phase.
Comparative studies of abrasive wear of “pure” phases and composites performed in different environments showed differences between dominating wear mechanisms. Tests results proved that the influence of the second phase presence in the materials was significant for the wear rate in wet environment of work. The wear resistance of investigated “pure “ phases and composites under dry conditions was practically the same.
The work was supported by the Polish Ministry of Science and Higher Education under AGH - University statutory works program for 2014.
References
[1] ASTM G65-94 Test Method for Measuring Abrasion Using the Dry Sand/Rubber Wheel Apparatus
[2] ASTM G75-95 Test Method for Determination of Slurry Abrasivity (Miller Number) and Slurry Abrasion Response of Materials (SAR Number)