Properties of the Ti-C-H-Сu composites obtained by mechanosynthesis using organic media

Abstract

Composites of a Ti-C-H-Cu system were obtained by mechanosynthesis in liquid carbon media (petroleum ether, xylene) followed by magnetic pulse compaction of the powders at 500°C in vacuum with the pressure amplitude of about 1.5 GPa. The chosen proportion of the components (Ti, Cu) corresponded to the composition TiC (90 vol%) -Cu (10 vol%). In addition, composites containing Cr and / or Ni with the atomic ratio of concentrations Cu : (Cr,Ni) equal to 80 : 20 were obtained. The compacts obtained had the diameter of 10 mm and thickness of 3 to 5 mm. The structure and phase composition of the composites were studied and density, microhardness and wear resistance were determined. The composites processed had the density of 87 -95 % of the theoretical value. The mechanosynthesis process in petroleum ether is not complete in 3h, since in the phase composition of compacts one observes, apart from intermetallic phase CiTi 2 and titanium carbohydride Ti 2 CH 0.6 , a significant amount of the initial Ti. The composites exhibit a layered microstructure. Use of xylene for mechanosynthesis process of the same duration allows one to obtain two-phase composites Ti 2 CH 0.6 + CuTi 2 . An increase of the duration of mechanical treatment up to 6 h leads to a formation of intermetallic CuTi in the phase composition of the composites obtained. Use of xylene allows one to obtain also 10 -20 vol% of nonstoichiometric carbide TiC. The microhardness of about 5 GPa was obtained for all the composites studied. Abrasive wear of the composites is an order of magnitude lower than that of steel U13. Alloying with Ni and / or Cr leads to some decrease of wear resistance due to a decrease of the quantity of TiC phase.

SPS of ”Titanium Carbide/Carbohydride – Copper” Composites

“…Under milling in liquid hydrocarbons, the formation of titanium The Ural school-seminar of metal scientists-young researchers carbide proceeds through an intermediate stage of the formation of carbohydrides, as described in Ref. [1][2][3]. To accelerate the processes of the carbide formation, additional sources of carbon (graphite, carbon black, etc.…”