THE INFLUENCE OF VC-AL ADDITIVE CONTENT ON STRUCTURE AND PHASE COMPOSITION OF cBN BASED SUPERHARD MATERIALS

  • K. V. Slipchenko V. N. Bakul Institute for superhard materials of NAS of Ukraine
  • I. A. Petrusha V. N. Bakul Institute for superhard materials of NAS of Ukraine
  • V. Z. Turkevich V. N. Bakul Institute for superhard materials of NAS of Ukraine
  • V. M. Bushlia Division of Production and Materials Engineering, Lund University
  • J.-E. Ståhl Lund University
Keywords: high pressure apparatus, superhard ceramics, cBN, phase composition, structure, vanadium

Abstract

Ceramic matrix materials based on cubic boron nitride with additives of vanadium carbide and aluminum were obtained by high pressure high temperature sintering. Sintering was carried out under pressure 7.7 GPa, in the wide temperature range of 1450 - 2450 °C. Three compositions containing 50, 60 and 65 vol.% of cBN were selected for investigation, 5% by volume of aluminum introduced into the mixture as oxygen geter. This paper presents the results of the study of the phase composition, microstructures and mechanical properties. It was found that the variation of the additive content has no effect on the shear modulus of composites, the highest values of microhardness were obtained in composites sintered in the temperature range of 1850 - 2150 °C. Formation of aluminum oxide were detected in all studied systems when sinterinf temperature was higher than 2000 °C. Mechanical properties of developed materialsclose to commercial analogues of BL group materials. Cutting tool materials in system cBN-VC-Al can be used at high-speed processing of alloys on the basis of iron

Published
2018-06-14
Issue
Vol 21 (2018): Rock Destruction and Metal-Working Tools – Techniques and Technology of the Tool Production and Applications
Section
Instrumental, structural and functional materials based on diamond and cubic bor