Development of Al2O3-based hybrid ceramic matrix composite coating to mitigate the erosive wear of advanced steel.

Steels are susceptible to surface- and subsurface-related degradations (e.g. corrosion and wear) depending upon the working environment; however, desired properties can resolve these issues. The authors have selected the high-velocity oxygen-fuel process to develop alumina-based composite coatings on ASME SA 387 GR22 CL2 steel. The coating material chosen comprises ceria and hexagonal boron nitride as the reinforcements. The metallurgical characteristics of coatings are recorded using X-ray diffraction and scanning electron microscopy. Mechanical properties are mapped using a nano-indenter; and an air jet erosion test rig is used to evaluate erosion wear response. Improvements in the mechanical properties and erosive wear resistance of the hybrid coating are attributed to microstructural changes and the generation of new phases. The values of H E , H E 2 , and H 3 E 2 are used to develop the mechanistic understanding of coatings' erosion behavior. Splat cracking and splat detachment are the observed erosion wear mechanisms. [ABSTRACT FROM AUTHOR]