Oct 22, 2015 Off Comments in Powder Coating by

Metal finishing meets the many challenges the medical device industry faces—strict sanitation, reliability, varying size—all while providing optimal performance.

In the medical industry, devices are used both internally and externally, so biocompatibility is critical. The process begins with raw bar stock or sheet stock being made into some kind of instrument that ends up being clean, defect-free and burr-free to meet stringent regulatory demands and undergo rigorous biocompatibility testing.

Many areas of medicine, including orthodontics, dental and even veterinary, face biocompatibility challenges, with orthopedic and cardiovascular implants being some of the most common. Orthopedic devices continue to evolve, and new implants for knees, hips, shoulders and elbows are rapidly being developed. Cardiovascular implants including defibrillators, pacemakers and artificial heart valves all have metal in them and need to stand up to blood in the human body.
Advantages of Electropolishing for Medical Devices

Certifications such as the ISO 13485 are designed to help manufacturers meet the medical device industry’s stringent demands. This requirement of higher quality finishes and standards is unique, but not surprising, considering the many specialized applications and concerns in the medical field, such as the spread of pathogens or “superbugs.” Although many may be disposable, devices must have smooth, corrosion-resistant surfaces that will not harbor bacteria.

Electropolishing is an ideal final finishing process for medical, and no comparable process can achieve the same high quality finish. Many manufacturers, for instance, specify passivation, which is sufficient for certain applications, because it can effectively clean and remove free-iron from the part’s surface. However, passivation does not produce the microfinishing and levels of corrosion resistance of electropolishing.

Some alloys, such as stainless steel, will naturally offer some corrosion resistance. However, any impurity on the surface (such as oil) will inhibit stainless steel from maintaining its natural state and corrosion-free surface.

Other commonly used mass finishing processes such as tumbling or burnishing can remove burrs and certain defects, but an additional process is still required to achieve the final micro finish. Pickling and other processes are unable to produce the required finish, and plating, for example, may ultimately result in peeling and flaking that may cause adverse reactions.

Color anodizing is also widely used by medical device manufacturers; with the FDA’s recent passing of the Unique Device Identifier enactment, it can help identify and match up surgical components. Laser marking can also be effective for identifying parts, but the uniqueness of electropolishing is that a single operation can achieve all of these benefits.

Read more: Cleveland Ohio Powder Coating: The Need for Metal Finishing in the Medical Device Industry