Affiliation:
1. North University of China, School of Mechanical Engineering 1 , Taiyuan 030051, China
2. North University of China, School of Materials Science and Engineering 2 , Taiyuan 030051, China
Abstract
In this study, we employed high-current pulsed electron beam technology (HCPEB) to modify NiCoCrAlY coatings that were created via laser cladding on 17-4PH stainless steel. We compared and analyzed the hot corrosion behavior of the coatings before and after HCPEB irradiation using a molten salt of 75 wt. %Na2SO4 + 25 wt. %NaCl at 700 °C. We also elucidated the mechanism by which irradiation affects the hot corrosion performance of the coatings. Our findings demonstrate that the irradiated coating surface exhibited a dense remelting layer, which effectively prevented erosion by oxygen and molten salt, without any internal oxidation corrosion. Moreover, irradiation refined the grains on the coating surface and increased the diffusion rate of grain boundaries. Consequently, the irradiated coating formed laminated thermal growth oxides (TGO) during the hot corrosion process, with the interface between the TGO and the coating always covered by an Al2O3 layer. This TGO structure provided excellent protection, reduced the corrosion weight gain, and corrosion rate of the coating, and significantly improved the hot corrosion performance of the coating.
Funder
Primary Research and Development Plan of Shanxi Province
National Natural Science Foundation of China
Research Project of Shanxi Scholarship Administration Committee
Subject
Surfaces, Coatings and Films,Surfaces and Interfaces,Condensed Matter Physics