Microstructural evolution and mechanical properties of NiCrAlYSi plus NiAl/cBN abrasive coating coated superalloy during cyclic oxidation

Cyclic oxidation behavior of NiCrAlYSi + NiAl/cBN abrasive coating at 900 degrees C and the mechanical properties of the coating-substrate system were investigated. Results indicated that elemental interdiffusion occurred between the coating and substrate, which caused the formation of interdiffusion zone (IDZ) and secondary reaction zone (SRZ) during aluminization, while their compositions and structures changed with oxidation. AlN interfacial layer formed at cBN/metallic matrix interface during aluminization, while it transformed into multilayer oxides during oxidation. Due to the microstructural evolution of these interfaces, the fracture behavior and bending toughness of the system changed greatly during three-point bending tests. Besides, the damage mechanisms were discussed. (C) 2021 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

The cyclic oxidation behavior of a NiCrAlYSi + NiAl/cBN abrasive coating at 900 degrees C was studied, revealing elemental interdiffusion and the formation of interdiffusion zone (IDZ) and secondary reaction zone (SRZ) during aluminization. Changes in composition and structures were observed during oxidation, affecting the mechanical properties of the system. The transformation of the AlN interfacial layer during aluminization and oxidation also impacted the behavior of the coating-substrate system.