Evaluation of Heat Resistance and Thermal Conductivity of Ni–Cr–Al System Layered Coatings

In this study, calculations and experiments were used to obtain the thermal conductivity equivalent coefficient value of layered (Ni2Al3 + CrAl7)/Cr20Ni80 coatings. The changes in the chemical composition because of the mutual diffusion of components, which determine the coating heat resistance, were analyzed. The simulation of the temperature field distribution over the cross section of the three-layer wall M1–Cr20Ni80–(Ni2Al3 + CrAl7) under conditions of reaching a stationary mode at an ambient temperature of 1600°C was performed using the DEFORM-2D software. The findings demonstrated that layered coatings (Ni2Al3 + CrAl7)/Cr20Ni80 could be considered heat-resistant and thermal barrier coatings. Such coatings provide high rates of high-temperature oxidation protection of copper air tuyeres of blast furnaces with minimal heat losses.