Multiscale topology optimization of biodegradable metal matrix composite structures for additive manufacturing

•Multiscale topology optimization for designing biodegradable metal matrix composite structures.•Multiphysics coupling model for simultaneously simulating the material degradation and macrostructural performance.•The optimized BM-MCS has better time-changeable stiffness to match bone healing.•The fabricated prototypes demonstrated the feasibility of the proposed print-then-cast manufacturing process.