In this article, a large-scale electromagnetic-thermal-mechanical co-simulation solver is implemented, to simulate complex radio frequency components by using a high performance computing framework. The proposed solver integrates the frequency-domain electric field simulation, with time-domain thermal and thermal-induced stress simulations, via a multiphysics coupling iterative process. In order to speed up the cosimulation, a Krylov subspace method with a domain decomposition method (DDM) preconditioner is used. First, the developed multiphysics solver is verified with the commercial software COMSOL Multiphysics. Then, the parallel performance of our cosimulation solver, with different ghost mesh thicknesses, is tested on a supercomputer. Finally, some multiphysics results of filters and a real-world system-in-package (SiP) are obtained with our proposed solver.