Abstract: The Interfacial bonding energy between coating and substrate for lowplasma sprayed materials was analyzed by theory and experiment. The plastic deformation energy, superficies modification energy and interfacial fracture surface energy consumed by samples during interfacial indentation experiment were determined by Knoop interfacial indentation method. Knoop interfacial indentation energy testing method was newly established. The interfacial fracture surface energy was obtained through research on interfacial bonding energy between coating and substrate for low-plasma sprayed Fe-based Ni/Fe and Cu-based Cu/Ni materials. Microanalysis for interface shows that the coating of Ni-based Cu/Ni material is porous and there exist many cracks at the interface between coating and substrate, moreover, no element diffusion layer is found in the coating and substrate. The bonding between the coating and substrate for Ni/Fe material is dense and there is an element diffusion layer with the thickness of about 2～3μm.
Interfacial bonding energy between coating and substrate for low-pressure plasma sprayed materials
Abstract：
The Interfacial bonding energy between coating and substrate for low plasma sprayed materials was analyzed by theory and experiment. The plastic deformation energy, superficies modification energy and interfacial fracture surface energy consumed by samples during interfacial indentation experiment were determined by Knoop interfacial indentation method. Knoop interfacial indentation energy testing method was newly established. The interfacial fracture surface energy was obtained through research on interfacial bonding energy between coating and substrate for low plasma sprayed Fe based Ni/Fe and Cu based Cu/Ni materials. Microanalysis for interface shows that the coating of Ni based Cu/Ni material is porous and there exist many cracks at the interface between coating and substrate, moreover, no element diffusion layer is found in the coating and substrate. The bonding between the coating and substrate for Ni/Fe material is dense and there is an element diffusion layer with the thickness of about 2～3?μm.
Fig.4 Elastic/plastic Knoop indentation model (F—Load; h—Plessed depth; h—Depth of press-in ρ—Zone of plastic yielding; a—Depth of indentation semi-elliptic crack; c—Length of indentation semi-elliptic crack; d—Size of long diagonal line of identation)
