Plasma electropolishing of components made of copper, steel, and alloys of zinc, nickel, chromium, and other metals using a single-component electrolytic solution

The electrolytic solution used addresses the technical issue related to surface quality—specifically surface roughness, which in some cases must be very low. This improvement in surface roughness is achieved through this new plasma electropolishing (PEP) process.

How does it work?

The electrolytic solution used in this technology consists primarily of ammonium sulfamate. It is a single-component solution, free of the unpleasant odors typical of moderators, and is potentially environmentally friendly and non-toxic. It is also reusable, as it converts the metal layers into a basic compound without altering the initial composition.

The solution acts on two main groups of metals: copper alloys (and pure copper) and steel alloys (e.g., 316L, 17-4PH, and similar). The polishing effect on steel is more uniform compared to the electrolytes described in the literature, preventing areas of corrosion. It is less sensitive to variations in composition and purity typical of 3D printing, ensuring greater reliability on particularly rough surfaces.

Applications

• Medical and Dental Devices: PEP ensures ultra-smooth, biocompatible surfaces that reduce bacterial adhesion and improve sterilization;
• Aerospace and Automotive Components: PEP increases fatigue strength, reduces stress concentrations, and improves aerodynamic performance by smoothing surfaces;
• Equipment for the Food and Beverage Industry: PEP creates mirror-like finishes that prevent contamination and comply with strict health regulations;
• Chemical and Pharmaceutical Industries: PEP removes surface defects that could trap chemicals, improving durability and compliance with GMP standards.
• Luxury Goods and Consumer Products: High-end watches, jewelry, and items that require a premium, polished appearance without any signs of mechanical polishing;
• Energy Sector (Oil, Gas, Nuclear): PEP enhances surface passivation, extending service life under extreme conditions;
• Additive Manufacturing Service Providers: PEP offers a fast alternative to manual sanding or abrasive polishing, reducing labor costs and lead times by replacing a post-processing chain.

Advantages

• Faster polishing;
• Greater efficiency in reducing surface roughness;
• Can be applied to highly rough surfaces (such as those produced by 3D printing) without any preliminary steps;
• No corrosion products form in certain areas of the sample;
• Suitable for use on both copper (and its alloys) and steel, including welded materials or those composed of two different types of alloys (e.g., copper and 316 stainless steel);
• Single-component, effective on two different types of metals (copper and steel).