Executive Summary : | Multicomponent alloys, particularly equiatomic NiCoCr alloys, have gained interest due to their strength and toughness. However, the ternary system in these alloys may limit thermal stability. Precipitation hardening is a strategy to improve thermal stability and mechanical properties, but it can change deformation characteristics. Preliminary investigations on the (NiCoCr)100-2x(AlTi)x (x=2,3) alloys have shown that precipitate hardening is strongly dependent on the alloy's microstructure, specifically dislocation density and grain size. This project aims to study the role of microstructure on the diffusion-controlled precipitation process, as atomic diffusion in multicomponent alloys is expected to differ from conventional alloys. The study will also investigate the influence of minor alloying elements like Mo and W on thermodynamic and kinetic parameters. The project will conduct nano-indentation and uniaxial mechanical tests over a wide temperature range (30C - 800C) and conduct detailed microstructural investigation to characterize deformation processes. The outcome is expected to provide new insights on precipitation kinetics in multicomponent alloys and develop design principles for high-temperature structural materials. |