Influence of heat treatment on the abrasive wear resistance of a Cr3C2NiCr coating deposited by an ethene-fuelled HVOF spray process

Sliding and abrasive wear behaviour of HVOF- and HVAF-sprayed Cr3C2–NiCr hardmetal coatings

“…More specifically, a previous study reported carbon loss and increased Ni content after HVOF-processing of Cr 3 C 2 -NiCr powders: approximately 31 wt.% and 39 wt.% Ni were found in two different coatings, both obtained from powders having a nominal Ni content of 20 wt.% [53]. The rebounding of chromium carbide grains was proposed as an important mechanism leading to the observed composition changes during spraying [53], a finding which has also been mentioned in other studies [9,38]. Carbide grains that exhibit microcracks and/or poor bonding to the matrix (Section 3.1 and Fig.…”

“…Moreover, in spite of the existence of some comparisons between Cr 3 C 2 -NiCr coatings obtained by the latest generation of HVOF and HVAF processes under erosion, abrasion and sliding wear conditions [9], a detailed examination of the sliding wear behaviour of HVOF-and HVAF-sprayed Cr 3 C 2 -NiCr coatings is not yet available. Although the characteristics of the feedstock powder are known to affect the properties of the thermally sprayed Cr 3 C 2 -NiCr coatings [29,35,36], the corresponding studies are not abundant, apart from some recent work by some of the authors on erosive and abrasive wear [8,9,37,38].…”

Microstructure and Wear Resistance of TIG Remelted NiCrBSi Thick Coatings

“…e wear mass losses of the sprayed and remelted coating are 0.2102 mm 3 and 0.0357 mm 3 , respectively, and the latter is only 17.1% of the former. erefore, the wear property of remelted coating has been significantly improved after remelting.…”

“…erefore, the microstructure of the remelted coating has become more compact and uniform, and its hardness is increased. (2) Although there are some hard phases, such as Cr 7 C 3 and Cr 2 B, and a part of unmelted or semimelting particles in the sprayed coating, the research by Ohmori et al shows that the interfacial bonding area of sprayed coating is generally less than 1/3 of the total interface and 2/3 or more is the unbound interface, which are unfavourable for the hardness [23]. However, after the remelting, the microstructure of remelting coating becomes more compact and uniform, a large number of dispersed carbides formed, and the harden phases such as fine skeleton like Ni 3 B, CrB, and Cr 23 C 6 disperse evenly in γ-Ni, which makes the hardness of remelted coating increase and uniform.…”

“…Because of their high ability to withstand extremes of temperature, excellent wear resistance, and high corrosion properties, Ni-based self-fluxing alloy coating has been widely used in petroleum, chemical, power, defense, and other fields [1][2][3]. At present, Ni-based self-fluxing alloy coating is mainly prepared by flame spraying and plasma spraying.…”