The performance of Ni-based single crystal superalloys, known for their exceptional high-temperature properties, is highly correlated to their unique γ/ γ' microstructure. It is known that the shape and size of the γ’ precipitates highly influence the macro-scale thermomechanical responses. Here, the magnitude of the natural lattice misfit between the γ and γ’ phases plays the most important role to establish a controlled size and distribution of precipitates during heat treatments. On the other hand, the effective lattice misfit, viz. the misfit during deformation, is, therefore, strongly dependent on the loading conditions and is a crucial factor in the directional coarsening of γ’ phase, known as rafting. The present study, using a Phase-Field model, will focus on demonstrating the role of the natural and effective lattice misfits on the microstructural stability at high-temperature and, therefore, on the performance of superalloys.