Searching for a suitable replacement for cobalt-based alloyssuch as Stellite 6 [1], which is used in wear-resistant coatings for nuclear applications, high entropy alloys, or more accurately complex concentrated alloys (CCA), have shown some promising properties [2]. Alloying elements where chosen considering the chemical composition of the substrate to ensure chemical and mechanical compatibility. In our case, this is 316L stainless steel, which is the most used material in valves and control rods. CCA coatings should provide wear and corrosion resistance between room temperature and 400°C for long time cycles. Based on these considerations and previous works [3], we selected the Cr-Fe-Mo-Ti system. Our work aims to develop new alloys using an iterative methodology. It consists in creating a robust database using the CALPHAD (Calculation of phase diagrams) method to predict thermodynamic properties. Then we will perform solidification and equilibrium calculations of different alloys compositions. High-quality database requires reliable data, which will be obtained from the combination of electronic structures calculations by DFT (Density Functional Theory) method with our own experimental work. Using this tool, we will design coatings alloys using additive manufacturing techniques according to favourable microstructures. Finally, tribology and corrosion tests will be performed on these samples. In this presentation, we will focus on CALPHAD modelling. We will discuss constitutive binary systems adopted from the literature, and we will assess constitutive ternaries.