Microstructure and transient oxidation behavior of NiCoCrAlYSiHf coating modified via high-current pulsed electron beam

Abstract

In this study, NiCoCrAlYSiHf coatings deposited via arc ion plating technique were modified by high-current pulsed electron beam (HCPEB) irradiation with different pulses. The coarse surface of the original coating was completely modified, and the modification effects of HCPEB irradiation, including surface finishing, composition optimization, and microstructural adjustment were obtained. The transient oxidation behavior of original and irradiated coatings was comparatively investigated under 1100 °C for 10 h. Experiment and characterization results showed that the remelting effects induced by HCPEB irradiation could greatly influence the growth behavior of the thermally grown oxides (TGO), presenting as the rapid formation of a complete and dense α-Al 2 O 3 layer in the transient oxidation stage, which guaranteed the protective effect of the AIP- M CrAlY X type coatings in subsequent oxidation stages. • NiCoCrAlYSiHf arc ion plated coating was modified via HCPEB technique with different parameters. • HCPEB irradiation led to a complete surface remelting, and eliminates original surface defects. • Nano-scale grains and deformation structures were obtained. • A stable, continuous and uniform α-Al 2 O 3 scale can be expected for all of treated coatings. • HCPEB technique is an effective approach to improve the performance of M CrAlY X -type coatings.