"Binder jetting is an economical and rapid additive manufacturing process that offers vast opportunities to combine a variety of materials, yielding interesting and useful properties. However, binder jetted parts, which can involve at least one hard and one soft material, can be more susceptible to corrosion and wear compared to conventional single alloy components produced by laser sintering or other high-temperature processes. This paper discusses the electroless nickel coating on 420 Stainless Steel and Bronze Binder-Jetted Composites(BJC). Electroless nickel, a well-known coating to provide high corrosion resistance and hardness, was attempted on BJC. To produce high-quality smooth electroless nickel coatings, we attempted the Taguchi Design of Experiments. Our design of experiment involved important factors, such as the surface preparation methodology prior to electroless nickel coating. During electroless nickel coating, we investigated the role of phosphorus content, temperature, and time in the production of smooth deposition. Optical microscopy was performed for qualitative and quantitative analysis. We also performed SEM to investigate the microstructure of different electroless coatings on BJC. Interestingly, all the combinations of parameters used in the electroless nickel coating produced different microstructures. We found that surface preparation was a critical factor in determining the smoothness of the film. We also showed that the dependent on the Ni solution’s phosphorus level and temperature. Our research ng insights for improving the usefulness of a wide variety of BJC by various coatings."
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Plasma Electrolytic Oxidation Ceramic Coatings on Zirconium (Zr) and Zr-Alloys: Part-II: Properties and Applications
A plasma electrolytic oxidation (PEO) is an electrochemical and eco-friendly process where the surface features of the metal substrate are changed remarkably by electrochemical reactions accompanied by plasma micro-discharges. A stiff, adhesive, and conformal oxide layer on the Zr and Zr-alloy substrates can be formed by applying the PEO process. The review describes recent progress on various applications and functionality of PEO coatings in light of increasing industrial, medical, and optoelectronic demands for the production of advanced coatings. Besides, it explains how the PEO coating can address concerns about employing protective and long-lasting coatings with a remarkable biocompatibility and a broad excitation and absorption range of photoluminescence. A general overview of the process parameters of coatings is provided, accompanied by some information related to the biological conditions, under which, coatings are expected to function. The focus is to explain how the biocompatibility of coatings can be improved by tailoring the coating process. After that, corrosion and wear performance of PEO coatings are described in light of recognizing parameters that lead to the formation of coatings with outstanding performance in extreme loading conditions and corrosive environments. Finally, a future outlook and suggested research areas are outlined. The emerging applications derived from paramount features of the coating are considered in light of practical properties of coatings in areas including biocompatibility and bioactivity, corrosion and wear protection, and photoluminescence of coatings
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- Award ID(s):
- 1827745
- PAR ID:
- 10331300
- Date Published:
- Journal Name:
- Coatings
- Volume:
- 11
- Issue:
- 6
- ISSN:
- 2079-6412
- Page Range / eLocation ID:
- 620
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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