In this study, we also investigate nickel deposition on EP, CP, and as-built AM components using electroless nickel solutions. Electroless nickel plating is a method of alloy treatment designed to increase manufactured component’s hardness and surface resistance to the unrelenting environment. The electroless nickel plating process is more straightforward than its counterpart electroplating. We use low-phosphorus (2–5% P), medium-phosphorus (6–9% P), and high-phosphorus (10–13% P). These Ni deposition experiments were optimized using the L9 Taguchi design of experiments (TDOE), which compromises the prosperous content in the solution, surface finish, plane of the geometry, and bath temperature. The pre- and post-processed surface of the AM parts was characterized by KEYENCE Digital MicroscopeVHX-7000 and Phenom XL Desktop SEM. The experimental results show that electroless nickel deposition produces uniform Ni coating on the additively manufactured components up to 20 μm per hour. Mechanical properties of as-built and Ni coated AM samples were analyzed by applying a standard 10 N scratch test. Nickel coated AM samples were up to two times scratch resistant compared to the as-built samples. This study suggests electroless nickel plating is a robust viable option for surface hardening and finishing AM components for various applications and operating conditions.
Characterization of Electroless Nickel-Phosphorous Plating Roughness and Thickness on Binder-Jetted 420 Stainless Steel Infiltrated with Bronze
"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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- Award ID(s):
- 1914751
- NSF-PAR ID:
- 10333055
- Date Published:
- Journal Name:
- Additive manufacturing
- ISSN:
- 2214-7810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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