Ceramic films were obtained on commercial pure aluminum by plasma micro-arc discharge,adding in the(NaPO3)6 for assisting-discharge in the CO(NH2)2 electrolyte system.XRD was used to investigate phase compositions of the modified layers with different concentrations of CO(NH2)2.Chemical composition and binding energy of the treated sample surface were studied by XPS.SEM was employed to analyze the morphology and thickness of ceramic film.The results show that the polycrystalline-ceramic layers of AlN on the...