Clad TiCrC(Ni) Composite Powders for Thermal Spraying of Coatings

The carbonyl cladding method was employed to produce metal–ceramic TiCrC(Ni) composite powders from double titanium–chromium carbide with 17, 25, and 33 wt.% Ni. To deposit coatings through the plasma, detonation, and high-velocity oxygen fuel spray processes, powder materials of different size fractions, μm, were produced: −80+40, −63+40, and −40+20, respectively. The composite TiCrC(Ni) powder particles were of irregular shape and consisted of a refractory core with 18–26 GPa microhardness, surrounded by a ductile nickel layer. Electron microprobe analysis revealed that the ceramic core included two phases: main TiCrC phase and interspersed Cr7C3 phase. The nickel layer deposited on the titanium–chromium carbide particles became thicker with higher nickel content of the TiCrC(Ni) composite powders and varied from 0.5 to 4 μm. The effect of nickel content on the service properties (apparent density and flowability) of the developed powders was determined. The apparent density of the TiCrC(Ni) powders was not found to substantially depend on their particle size or nickel content and was 2.3–2.6 g/cm3 on average. The flowability of the TiCrC(Ni) powders was found to depend on their particle size and nickel content. The flowability of the TiCrC(Ni) powders improved with increasing particle size and was 41.2–51.4 sec for the −63+40 μm powders and 40.2–47.0 sec for the −80+40 μm powders. The −40+20 μm TiCrC(Ni) powders for oxygen fuel spraying had very poor flowability and thus could be used only for coating deposition units with forced powder supply to the spray area. Their flowability became higher with nickel content of the TiCrC(Ni) composite powders increasing from 17 to 33.5 wt.%.