Everything You Need to Know About Chemical Milling

Chemical milling is a metal surface treatment process used to remove a small amount of material from metal parts as part of mechanical operations. The process uses liquids with some type of chemical additive to remove material from a workpiece. There are two types of chemical milling. They include chemical etching and polishing, which are the processes of removing material by dissolving it and then reprecipitating it.

What is the Difference Between Chemical Etching and Chemical Polishing?

There are three primary methods in chemical etching: immersion, spray or flow, and brush. This means that all three methods come into contact with the metal surface to remove the material with chemicals. Chemical polishing involves mechanical abrasion by a brush or pad and a liquid chemical solution, also known as a slurry.

Chemical etching is often used to provide a fine surface finish on materials like aluminum and copper. It works best on clean surfaces with finished dimensions fairly close to the final size desired by the manufacturer. Etching can be used to create openings for electronics and other components that need to be milled later, but the actual milling can be done after the etching process has been completed without causing any damage to the underlying surface.

What are the Benefits of Chemical Milling?

Does not produce burrs

The key benefit of chemical milling is that it does not produce burrs. The traditional methods of mechanical milling and machining can produce burrs, which are small pieces of metal left over after the job has been finished. A burr is a thin piece of leftover material that can cause problems when putting together a finished product. Chemical milling eliminates the possibility of creating burrs.

Easy processing of brittle materials

Chemical milling is a process that enables the easy processing of brittle materials. This is done by treating the material with a combination of chemicals that, when heated, dissolve the material’s surface and leave behind a porous surface structure. The resulting surface can be used as adsorption support for gas adsorption, ion exchange, and catalysis.

Lower tooling costs

Costs for chemical milling are typically about half of what it would cost for electroplating, which means that customers can enjoy products with higher-quality finishes at lower prices. This makes chemical milling an attractive option for companies that manufacture durable goods such as tools, automotive parts, and even jewelry. In addition, because chemical milling services exist in nearly every global market, manufacturers have access to an international network of certified professionals who can help them achieve the exact look they’re going for in their products. Chemical milling is also environmentally friendly since it doesn’t require harsh chemicals or heavy metals, and may even reduce corporate emissions.

Key Takeaway

Chemical milling is a process that uses chemical reactions to remove material from the surface of a workpiece. In the case of aluminum alloys, it is performed to remove material from the surface of an aluminum cast part to produce a smooth finish. The end result is a part with its surface area reduced by as much as two-thirds.