Microstructure, phase composition and corrosion resistance of Ni₂O₃ coatings produced using laser alloying method

Abstract

A B S T R A C TThe paper presents the studies' results of microstructure, microhardness, cohesion, phase composition and the corrosion resistance analysis of C45 steel after laser alloying with nickel oxide (Ni2O3). The aim of the laser alloying was to obtain the surface layer with new properties through covering C45 steel by precoat containing modifying compound, and then remelting this precoat using laser beam. As a result of this process the surface layer consisting of remelted zone and heat affected zone was obtained. In the remelted zone an increased amount of modifying elements was observed. It was also found that the surface layer formed during the laser alloying with Ni2O3 was characterized by good corrosion resistance. This property has changed depending on the thickness of the applied precoat. It was observed that the thickness increase of nickel oxides precoat improves corrosion resistance of produced coatings.

Two-Dimensional Earth-Abundant Transition Metal Oxides Nanomaterials: Synthesis and Application in Electrochemical Oxygen Evolution Reaction

“…The Co 3 O 4 nanosheets showed the crystalline plane of (311), in which the peak obtained at an angle (2θ) of 37.1 with low intensity, revealing the spinel structure , as depicted in Figure (a). The XRD peaks of NiO nanosheets (Figure b) at 37.2, 43.2, 62.5, and 76.3 were indexed to the planes of (111), (200), (220), and (311), respectively for cubic NiO crystallites (marked as #) The other peaks obtained at an angle (2θ) of 34.3 and 51.2 were assigned as the planes of (002) and (202), respectively for cubic Ni 2 O 3 (marked as *). , A intense peak also observed at 44.3 corresponded to the plane (111) (marked as †). Figure c displays the XRD pattern of the CuO nanosheets.…”

Tribology of nitrided-coated steel-a review

“…Fig. 9 represents the distinction between acceptable and unacceptable failure criteria in adhesion test [16]. The adhesion quality of the coat can be evaluated by comparing the indentation pattern.…”

“…9. Distinction between acceptable and unacceptable failure in adhesion test [16] Adhesion evaluation of untreated & prenitrided samples was carried out [1] and results suggest that surface roughness, coating material, and type of nitriding have an influence on the coating-nitrided substrate adhesion. Table 2 shows the results obtained by Zeghni and Hashmi [1].…”

The Effect of Electrolyte pH on the Ni-Co Mixed Oxides Coatings Produced from Citrate Baths

“…Moreover, there is a great availability of the equipments used to obtain these coatings [1][2][3] . Thin nanostructured oxide layers produced by electrodeposition have been used as appropriate materials for different electrochemical processes, ranging from anticorrosive to electrocatalytic properties [4][5][6][7][8][9] . Among the electrocatalytic coatings, there is a great interest in those useful to enhance the O 2 and H 2 evolution reactions (respectively, oxygen evolution reaction -OER, and hydrogen evolution reaction -HER), which are important in several technological processes, such as water electrolysis, fuel cells, batteries and sensors 1,[10][11][12][13][14][15][16][17] .…”