Creation of nickel aluminite by the thermoreactive diffusion technique and investigation of its properties

Nickel-based superalloys are an exceptional class of metallic materials with high temperature resistance, toughness and resistance to plastic deformation and high oxidation resistance. These materials are commonly found in aircraft and power generation turbines, rocket engines, and other harsh operating environments including nuclear power and chemical processing plants. TRD technique is a method developed to obtain hard and wear-resistant carbide, nitride, carbonitrid, aluminite and silicide-based coatings on the surface of steels. In TRD technique, there is a controlled formation on the substrate surface. There are many application areas where this technique is used. Due to the formation of hard layers with TRD, it is used in molds, cutting tools, knives, auto parts, parts used as guides in the textile industry. Diffusional coatings can be produced by various methods, mainly box cementation processes and chemical vapor deposition (CVD). In this study, nickel aluminide-based coating layers were formed on the surface of pure nickel substrate materials, the surface of which was prepared metallographically, by aluminizing with the thermoactive diffusion technique. The process was carried out in an aluminum-based powder environment at 600°C, 700°C and 800°C temperatures and 2, 4 and 6 hours. The properties of the coatings formed on the surface were revealed by making microstructural examinations, phase analyzes, hardness measurements, corrosion testing and oxidation experiments. In the study, it was observed that the coating formed on the nickel surface was successfully obtained and had a homogeneous and well-bonded porosity-free structure with 20-250 µm thickness, consisting of Ni3Al2 and NiAl based phases and a hardness of 780-1050 Hv0.02 and corrosion and oxidation resistant.