Oxidation and Hot Corrosion Resistance of HVOF WC-NiCrFeSiB Coating on Ni-and Fe-based Superalloys at 800 ℃
The present work evaluates the oxidation and hot corrosion resistance of high velocity oxy-fuel (HVOF) sprayed WCNiCrFeSiB coating deposited on Ni-based superalloy (Superni 75) and Fe-based superalloy (Superfer 800H). The coated as well as uncoated specimens were exposed to air and molten salt (Na2SO4-25％NaCl) environment at 800 °C under cyclic conditions. The thermogravimetric technique was used to establish the kinetics of corrosion. The corrosion products were characterized using the combined techniques of X-ray diffraction (XRD), scanning electron microscopy (SEM) and electron probe micro analyser (EPMA). The WC-NiCrFeSiB coating provides necessary resistance against oxidation and hot corrosion to both the nickel and iron based superalloys in the given environmental conditions at 800 0C. The oxides of active elements of the coatings, formed in the surface scale as well as at the boundaries of nickel and tungsten rich splats, have contributed for the oxidation and hot corrosion resistance of WC-NiCrFeSiB coatings, as these oxides act as barriers for the diffusion/penetration of the corrosive species through the coatings.
T.S. Sidhu A. Malik S. Prakash R.D. Agrawal
Metallurgical and Materials Engineering Department, Indian Institute of Technology Roorkee, Uttranchal, India
国际会议
北京
英文
2007-05-14（万方平台首次上网日期，不代表论文的发表时间）