Microstructure and physical properties of DLC films deposited by laser induced high current pulsed arc deposition

Diamond-like carbon (DLC) coatings were deposited on Si(100) and stainless steel substrates by laser induced high current pulsed arc (LIHCPA) system. A pulsed current more than 1 kA was generated on the target in order to make DLC coatings have higher hardness and denser structure. The experimental results have shown that the arc current had strong influence on the hardness and sp3 content of the DLC coatings. It has been observed that when the arc current was raised from 1 kA to 4 kA, the hardness increased from 28 GPa to 52 GPa, and the sp3 fraction of the DLC films measured by XPS increased from 47% to 61% accordingly. The corrosion behavior of DLC coatings were also studied in 0.5 M H2SO4 solution by using potentiodynamic polarization method. These results reveal that DLC coatings on stainless steel exhibited excellent corrosion behavior especially in lower corrosion current which was less than 4 × 10− 7 A/cm2.