Akisin Cletus John
PhD Researcher in thermal and cold spray additive manufacturing of high entropy alloys
High entropy alloys are a novel class of advanced engineering materials that consist of multi-principal elements (up to 5 or more) at near or equal atomic proportions. The development of these alloys is currently the focus of significant attention in materials engineering for industrial applications because the properties of the alloys potentially surpass those of conventional high-performance alloys. High entropy alloy can potentially form simple single-phase solid solutions as a multi-principal elements alloy, which is attributed to an increasing entropy of mixing as the number of elements increases in the alloy. The mechanism behind the formation of solid solutions in these new material systems—high entropy alloys, is still under investigation. Due to the unique characteristics and properties of high entropy alloys, they demonstrate the potential to form surface coatings for demanding environments.
Therefore, this project is set to manufacture high entropy alloy coatings using thermal and cold spray techniques. These are surface coating techniques that can be applied to additively manufacture high entropy alloys for harsh environments such as bond coat for thermal barrier coatings. The project is also involved with numerical simulation of high entropy materials under high-impact spraying process, thermodynamic modelling using techniques such as CALPHAD to design the alloys and predict phases during feedstock preparation, spraying and testing conditions. The high entropy alloy coatings will be tested for oxidation, wear, thermal-fatigue resistance, to enhance the surface properties of bulk materials both for technological and end-use.