The chemical and mechanical characteristics of thermally aged interference thin films on stainless steel

The chemical and mechanical stabilities of colored interference thin films on stainless steel were investigated by thermally aging these films at 150 °C for different aging times of 2, 4, 8, 16 and 256 h. The thermally aged films were morphologically characterized using field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM), and exhibited decreased porosity after thermal treatment. Fourier transform infrared spectroscopic (FTIR) analyses and depth sensing indentation tests confirmed that the sample aged for 2 h had better mechanical characteristics than samples that had not been thermally aged. Further, thermally aged samples exhibited increased hardness and abrasion wear resistance.