Study of Wear on Nicraly Coating Sprayed by HVOF on 316 Steel and Laser CO₂ Remelting Process

Abstract

The use of NiCrAlY is a great alternative as Bond Coat - BC (bonding layer) in coatings for turbine vane, and it is possible to increase its life. This work aims to study the BC layer of NiCrAlY on the substrate of 316 steel which was deposited by the High Velocity Oxygen Fuel method (HVOF) and after laser remelting irradiated. selective laser melting which is an innovative process. The laser treatment induced changes in porosity, microhardness and wear resistance. After spraying, the samples were irradiated with a CO2 laser beam by varying the scan speed in 50, 100 e 200 mm/s. The speed at which the metallurgical bond between the coating and the substrate occurred was of 50 mm/s. A wear test was performed to analyze the thickness of the coating, which was 60 μm, and the hardness profile and hardness profile where it presented a higher hardness in the coating after the laser treatment. The investigations range included analysis of top surface of coatings by XRD characterization oxides formed types and microscopic investigations of coatings morphology.

Enhancing the Oxidation Resistance of NiCrAlY Bond Coat by High-Current Pulsed Electron Beam Irradiation

“…The thermal barrier coatings have a development history of nearly 40 years, and their preparation process is constantly improving. From the initial atmospheric plasma spraying (APS), to low-pressure plasma spraying (LPPS), in addition to high velocity oxy-fuel spraying (HOVF), laser cladding, electron beam physical vapor deposition (EB-PVD) and other methods [1][2][3][4][5][6][7]. The bond coat of thermal barrier coatings prepared by atmospheric pressure and low-pressure plasma spraying methods has a lamellar structure, which is conducive to the improvement of thermal insulation performance of thermal barrier coatings.…”