Coatings characterization of Ni-based alloy applied by HVOF

Abstract

Purpose The thermal spraying technique of High-Velocity Oxygen Fuel (HVOF) coating was used to deposit coatings of an alloy composed of Ni-based substrates on stainless steel AISI 304. The aim of this study was to determine the mechanical properties such as hardness and bond strength that these coatings have when the spray distance is varied, as well as the microstructure and phases formed during the thermal spray process. Design/methodology/approach The coatings were applied by HVOF and characterized by scanning electron microscopy, image analysis, X-ray diffraction, microhardness and bond strength to analyze the mechanical properties. Findings The microstructure of the coatings showed low porosity, oxide content and interface contamination in the substrate–coating interface, without the presence of unmolten particles. The microhardness values reached 600 HV for the three spray distances used and the bond strength values reached over 55 MPa. Practical implications The use of coatings on aircraft components is growing dramatically owing to the high costs of advanced materials and the growing lifecycle requirements for high-performance systems, which are taken into account because of the variety of coatings and complexity of environmental factors. Originality/value The originality of this study lies in the development of new coating materials for the manufacture and protection of various turbine components. The value is based on the development of materials and processes to be used to manufacture them.

Cyclic high temperature corrosion studies of carbon nanotubes-Cr2O3 composite coatings on boiler steel at 900°C in molten salt environment

“…This results in enhance melting of matrix powder particles resulting in reduced porosity. The porosity values observed in this work are in good agreement with porosity values reported in previous literature for HVOF sprayed thermal spray coatings (Sidhu et al , 2017; Ksiazek et al , 2016; Gupta et al , 2015; Cabral Miramontes et al , 2018).…”

Microstructure Characteristics and Properties of NiCrMoFeCoAl-30%SiO₂ Composite Coating on T22 Boiler Tube Steel

“…XRD, HR-TEM, microhardness test, and SEM/EDAX techniques are used to characterize the HVOF coated sample and feedstock powder. Several investigations have evaluated entire coating designs [9][10][11][12][13]. Song et al [14] studied the high-temperature oxidation behaviour and microstructure of HVOF (gas and liquid-fuelled) sprayed Ni50Cr coated ASME P92 alloy in thermal power plants.…”

Microstructure Characteristics and Properties of NiCrMoFeCoAl-30%Cr₃C₂ HVOF Coating on T22 Boiler Tube Steel

“…In demanding operational situations, such as hostile environments, the covering of WC-Co and WC-CoCr exhibits better tribological structures [8][9]. Several investigations have been done on evaluating entire coating designs [10][11][12][13][14]. Cr 3 C 2 -based materials are often used to improve the complex application of high-temperature applications including abrasions, slides, soil erosion and stress [15][16][17][18][19][20][21][22][23][24].…”