Growing optimization of gas turbines in terms of mass, energy efficiency and lifespan requires an accurate knowledge of solid temperature loads and resulting thermomechanical stress, especially during the sudden engine speed changes transient phases. This study deals with the development of a coupling strategy at fluid solid interface for transient heat transfer problems.A quasi-dynamic method is used between a finite-volume fluid code and a finite-element solid code. At the fluid-solid interface, Dirichlet-Robin conditions are employed. Various coupling relaxation parameters are tested on a test-case of flat plate with transient boundary conditions. It’s shown that stability and computational cost increase when coupling relaxation parameter increase.