Microstructural features and thermal response of granulated Al and A356 alloy with relevant Sn additions

•Al-Sn and A356-Sn composite Phase Change Materials were produced with medium-rapid cooling rates, estimated by Finite Elements Simulations.•Microstructural features were evaluated in the view of possible application as Latent Heat Thermal Energy Storage form-stable systems.•Thermal responses were modeled by thermodynamic calculations and assessed by Thermal Analyses.•The form stability of the composites was assessed by dilatometric tests.