Predictive Modeling of Electroless Polyalloy Coating Properties Using Artificial Neural Networks

Electroless nickel (EN) plating offers a promising route to enhance the surface functionality, corrosion resistance, and mechanical durability of 3D-printed acrylonitrile butadiene styrene (ABS) components for applications such as EMI shielding, decorative trims, and lightweight structural parts. However, when conventional pre-treatment steps like sanding and chromium-based etching are eliminated for environmental and practical reasons, especially on complex geometries, surface preparation becomes a major challenge. This chapter investigates the failure modes and limitations of chromium-free EN plating on unsanded, FDM-printed ABS parts using a green surface treatment protocol involving Piranha solution etching and palladium activation. Several critical issues were observed, including incomplete surface activation, poor wettability, and non-uniform catalyst deposition—particularly within recessed features and fine details. These led to common coating defects such as blistering, delamination, patchy or thin deposits, and localized uncoated regions. The results underscore the need for tailored surface modification strategies that can address the intricacies of additively manufactured surfaces, highlighting the potential and current limitations of chromium-free EN plating in sustainable, high-performance polymer metallization.