In this work we evaluate the strategy of using 3C-SiC as a substrate for III-V nitrides heteroepitaxy (AlN, GaN…). Our methodology is based on the elasticity theory of strained interfaces and involves not only geometric parameters of host materials but also parameters related to their elastic properties. The basic physics involved in the theory correlates lattice dynamics and strain gradients via effective elastic constants associated with the host materials forming the heterosystem (S factor). Within this approach, the optimization of the IIIV/ 3C-SiC interface is achieved by applying, at the interface, continuity conditions to the host material S factors and the related geometric features. An alloyed layer, i.e. AlxGa1−xN, simulates the III-V compound. We find out that the optimizing composition of this layer is x=1 corresponding to a stoechiometric AlN layer. This is consistent with the result showing that AlN presents the closest structural characteristic to SiC. Our results also predict that, when used as a buffer layer, AlN may provide a mean to optimize the GaN/SiC interface.