Improvement of Tribological Properties of Metal Matrix Composites by Means of Slide Burnishing

  • Piotr BEDNARSKI University of North Texas
  • Dionizy BIAŁO Warsaw University of Technology
  • Witold BROSTOW University of North Texas
  • Kazimierz CZECHOWSKI Institute of Advanced Manufacturing Technology (IAMT)
  • Waldemar POLOWSKI Institute of Advanced Manufacturing Technology (IAMT)
  • Piotr RUSEK Institute of Advanced Manufacturing Technology (IAMT)
  • Daniel TOBOŁA Institute of Advanced Manufacturing Technology (IAMT)
Keywords: metal matrix composites, slide diamond burnishing, surface roughness

Abstract

Burnishing of metal surfaces can affect positively tribological and mechanical properties such as fatigue strength, wear resistance, contact stiffness and bearing capacity. Burnishing affects the entire surface topography, including surface roughness, radii of curvature of peaks and valleys, slope angles and more. We have studied A1Mg1SiCu (6xxx series) aluminum matrix composites with a reinforcing phase of Al2O3 which exhibits good workability but poor machinability. The second series studied was based on an AlSi alloy (A-390) reinforced with SiC – this one characterized by poor workability but good machinability. Materials have been prepared by mixing metal powders with the reinforcement, cold pressing, sintering, hot extrusion and heat treatment. We have determined surface roughness with a Hommel tester; the arithmetical mean for A1Mg1SiCu (A6061 + Al2O3) was ~1 µm before burnishing and ~0.15 mm after burnishing. We have also determined the bearing capacity at 50 % with the same tester: before burnishing 2.30 µm and 0.47 µm afterwards for A6061 + Al2O3; before 2.30 µm, afterwards 0.37 µm for A390 + SiC. Vickers microhardness at the surface with respect to the core increases 30 % for the Al2O3 containing composite and 50 % for the SiC containing composite.

DOI: http://dx.doi.org/10.5755/j01.ms.19.4.2404

Published
2013-12-11
Section
METALS, ALLOYS, COATINGS