The object of the work is wear resistant coatings manufactured by plasma spraying of powder composites with the following additional processing by pulsed plasma flows. The parameters of a compression plasma flow were: a diameter in the field of maximal compression - 0.03m, a rate of flow - (1-2)x10⁵m/sec, the temperature of plasma of 1,5-2x10⁴K. The action of plasma flow was executed in pulsed-periodic regime with pulse time of 200μs, a period of 15-30s and number of pulses in series of 2-10. The power density on sample measured by calorimeter was of 10⁵ - 10⁶ W/cm². The pressure on target surface was of 2-3MPa.
Investigated are pulsed plasma processing parameters of coatings, sprayed with NiCr--Fe+Cr₃C₂ powders. Determined are optimum technological regimes.
During investigation of NiCr+50(80)%Cr₃C₂ coating it is determined that an optimal power density was ~5x10⁵ W/cm², an optimum quantity of 200μs plasma pulses is 5. Therewith the fusion of a surface and underlying layers through the whole thickness of sprayed materials is reached. The density and cohesive strength of sprayed materials rises, a generalized index of porosity decrease on 15--20%. Such transformation of structure contributes to resistance of a coatings to mechanical destruction during a process of friction. At the same time the residual porosity and crumbled hard particles of carbide phase are present, what is apparently connected with shortness of thermal and dynamic impulse effects.
The obtained results may be used to increase durability of machine parts, which operate in conditions of intensive friction and wear – out.