Elastic Response of Plasma Electrolytic Oxidation Coated Open Cell Aluminium Foams

Duocel aluminium foams of two pore sizes were Plasma Electrolytic Oxidation coated to different thicknesses and tested in tension, using load-unload cycles to evaluate their stiffness behaviour. The coatings penetrated into the structure, albeit with reducing thickness for smaller pores. The coatings improved foam mechanical properties, particularly elastic modulus, however a higher rate of damage and smaller strain to failure was observed for the thickest coating. This is likely to be caused by degradation of the coating properties due to increased defect density as well as by general embrittlement of the associated composite foam material.