Oxidation behavior of micro- and nano-crystalline coatings deposited by series double-pole electro-pulse discharge

摘要

A new technique-series double-pole electro-pulse discharge (SDPEPD)-was developed as a surface coating process. In this process, both positive and negative poles of a pulse power were used as the depositing electrodes with the substrate alloy as an induction electrode. Several "pin-plate-pin" settings with the principle of SDPEPD were tested. Micro- and nano-crystalline stainless steel (Fe- 18Cr- 8Ni) coatings and oxide-dispersed stainless steel coatings were deposited on stainless steel surface. Oxidation at 950 deg C in ambient air showed that the coatings greatly improved the oxidation resistance of the steel. The addition of dispersed Y_2O_3 nano-particles into the alloy coatings was found to further reduce the scaling rate and enhance the oxide spallation resistance.