Abstract:

nd. The prevention of surface oxidation of high-temperature nickel-based alloys is possible by using diffusion coatings, composed of layers of barrier functions. The last inhibit undesirable redistribution of elements at high temperatures. Objective. The aim is to establish the possibility of education in the nickel diffusion titan-aluminum cover with a layer of (Ti,Zr)N, the research phase and chemical composition, structure, properties. Methods. The barrier layer is deposited by physical vapor deposition. Titanium colorizing has been carried out in the powder mixture of Ti, Al, Al2O3, NH4Cl in the container with fusible gate for 4 hours at 1050 °C. The obtained coatings were stu­­- died by modern methods of materials science: X-ray diffraction, microprobe, metallographic and other physic-methods. Results. The possibility of the coating formation on nickel with Ni2Ti4O, NiTi, Ni2AlTi, Ni3 (AlxTi1 -x) compounds, and the transition zone is established as well as the effect of the thickness of the barrier layer (Ti,Zr)N on the coating structure. The barrier layer thickness of 5.5–6.0 microns promotes the formation of jointing zone above the (Ti,Zr)N layer restricts a thickness of the transition zone, eliminates the formation of the Ni (Al,Ti) layer  in the jointing zone, and Ni (O)layer in the transition zone.Conclusions. It is found that during the process of titaniumaluminizing of nickel diffusion zone is formed on the basis of oxides, intermetallic compounds of titanium and aluminum, of (Ti,Zr)N layer with high micro hardness. The investigated coating may be promising for the production of nickel and its alloys at high temperature operating conditions.

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