The engineering of a component's surface is of remarkable importance, it allows applications that surpass what is achievable by the substrate alone by improving surface properties such as hardness, wear and corrosion resistance and even aesthetic value. This project focuses on obtaining bronze coatings through the diffusion of electrodeposited tin on copper via heat treatment. Specifically, the single phase α is targeted due to its attractive properties. Determining the correct heat treatment parameters is crucial since only a specific range of compositions lead to the formation of the desired microstructure and, consequently, properties. The diffusion of a thin coating of tin onto copper often leads to the formation of undesirable features: small craters containing different phases than the one targeted. In the present work, the diffusion behavior of tin-copper couple was investigated; a numerical model was developed to predict the composition profile after heat treatment, which agrees with experimental observations; and the mechanism for the formation of undesirable surface craters during heat treatment was studied and the probable solution proposed. II Acknowledgements