Cold spraying and laser cladding as an alternative to electroplating processes

Abstract

Purpose The purpose of this paper is to propose cold spraying and laser cladding processes as alternatives to cadmium and chromium electroplating, respectively. There are many substances or chemicals within the coating technology that can be identified as substances of very high concern because of their carcinogenic or mutagenic nature. Cadmium and chromium undoubtedly belong to these items and are the basic constituents of electrolytic coating processes. Finding an alternative and adapting to the existing restrictions of the usage of such hazardous products stands for many to be or not to be in the market. Design/methodology/approach The research work was focused on down selecting the appropriate materials, producing the coating samples, testing their properties and optimizing process parameters by statistical method. On the one hand, the high-pressure cold spray system and spraying of the titanium coating on the landing gear component, and on the other hand, the high-energy laser cladding facility and the wear resistant cobalt-based coating deposited onto the shock absorber piston. Substrates of these two applications were made of the same material, 4330 – high-strength low-carbon steel. Findings Meeting the requirements of Registration, Evaluation, Authorization and Restriction of Chemicals implies undertaking research and implementation work to identify alternative processes. The work provides the technical characteristics of new coatings justifying application readiness of the researched processes. Originality/value Taguchi’s design of experiment method was combined with the measurements and analysis of specified coating properties for the optimization of the cold spray process parameters. There is also laser cladding process development presented as a fast rate technology generating coatings with the unique properties.

Optimization of Mechanical Properties of Cr3C2-Ni20Cr/Graphite Cold Sprayed Coatings

“…Based on initial experiments, the following tested parameters were changed: the weight content of Nigraphite powder in the blend (A), gas composition (B), spraying distance (C), and traverse gun speed (D) (Table 2). The S/N coefficient was calculated for the following cases [22,23]: (a). for "the larger, the better" features (e.g., Cr 3 C 2 and graphite content in the coatings, hardness)…”

“…The selection of spray parameters can be the result of process modeling or the use of one of the experimental design (DOE) methods [1,18]. The Taguchi method is a tool used to optimize various processes in industry [19][20][21], including cold spraying [22][23][24]. In this paper, we experimented using the base powder Cr 3 C 2 -25(Ni20Cr), which has been used for many years to deposit wear-resistant coatings, mainly via HVOF spraying [25][26][27].…”

Microstructure and Tribological Properties of HVOF-Sprayed Nanostructured WC-12Co/Fe3O4 Coatings

“…Therefore, knowledge of the influence of spraying parameters on the properties of coatings is very important. Therefore, the use of statistical methods for optimizing spraying parameters is a very effective solution to this issue [26,27]. This is particularly interesting in the case of composite coatings consisting of both a nanostructured matrix and a nanostructured solid lubricant.…”

Current Research Status on Cold Sprayed Amorphous Alloy Coatings: A Review

“…At present, the preparation technology of amorphous alloy coatings mainly includes laser treatment and thermal spraying technologies, such as plasma spraying, high velocity oxygen fuel, and high velocity arc spraying [16]. The laser cladding technology utilizes the characteristics of rapid heating and rapid cooling, the energy density is between 10 4 -10 6 W/cm 2 , and the cooling rate of the molten pool can reach 10 4 -10 6 K/s [17]. The high energy density makes the cladding layer material and substrate material surface completely melt, resulting in an extremely thin molten pool depth.…”