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This paper introduces a new concept of coated fine carbides modified by nanoparticles Al2O3, ZrO2 (inhibitors) as the starting method for improved hardmetals. The study involved computational and experimental methods to determine functional relationships between the parameters of microstructure, sizes, volume content of additives of nanoparticles and properties (transverse rupture toughness, hardness, fracture toughness) of the heterophase hardmetal composites. Factors having a positive influence on the structure of hardmetals are the decrease in the average size and contiguity of carbide grains due to SPS-consolidation and ultrasonic activation during mixing. The study of microstructural parameters by scanning electron microscopy in a combination with x-ray phase analysis indicates high statistical homogeneity of the relative distribution of nanoparticles (inhibitors) in the cobalt binder between carbide grains and the formation of nanostructured inclusions in hardmetal composites.

The influence of nanoparticles additives on the hard metals properties has been investigated. Nanoparticles introduced into a binder of average size decrease the metal interlayer and therefore increase the strength of binder and composite as a whole. The reduction of the carbide grain average size was found as well (owing to nanoparticles blocking influence on re-crystallization). Besides, the internal thermotension and adhesion wear decrease at high speed cutting (especially for stainless steel) in comparision with base hard metals. The test results display that the modification through ultrafme particles enables to improve the main properties: wear resistance – 1.6 - 2 - fold; fracture toughness – 1.8 - 2 - fold; transverse rupture toughness - at 25 - 50%; tool life – 1.3 - 4 - fold.

The paper presents the results of experimental investigation of formation microstructure and properties of ultra high molecular weight polyethylene (UHMW-PE), modified by ceramics А12О3 particles by different particle size and method of obtaining.