NEE is one of the few metal finishers in the U.S. to concentrate exclusively on precision stainless steel electropolishing. By solely focusing on high quality electropolishing, we can handle the most challenging finishing and delivery requirements of our diversified customer base.
To help you better understand electropolishing, we’ve created this resource page that takes you through what electropolishing is, how it’s done, and why its such a good fit for any business looking to improve the appearance and/or performance of their stainless steel parts. Read along below in chronological order or jump to the section that interests you most:
- What is Electropolishing?
- The Electropolishing Process
- Top 5 Benefits of Electropolishing
- NEE’s Electropolishing Services
1. What is Electropolishing?
Electropolishing is an electrochemical and reverse plating process that removes the outer layer of skin on a metal part to address microscopic imperfections within its finish—instead of electroplating which deposits metal onto the finished surface. Electropolishing will smooth and streamline the microscopic surface of most metal objects—typically stainless steel or similar alloys. The process may improve the surface finish of your metal part by up to 50% (depending on part tolerances and surface finish) or more—rendering the surface of the metal microscopically featureless and void of any tiny imperfections. Often, during a standard run, total material removal is limited between 0.0002” to 0.0003” per surface—but removal rate can be adjusted depending on a part’s tolerances.
It’s important to note that electropolishing only improves the surface of a metal part on a microscopic level. Any macroscopic textures or surface scratches will only result in a smoother texture or smoothed scratch if taken though the electropolishing process. For macroscopic surface imperfections, mass finishing is the more appropriate process for the job.
2. The Electropolishing Process
The electropolishing process is initiated by immersing a metal part into a temperature-controlled bath of electrolyte (typically a mixture of sulfuric acid and phosphoric acid). The working part is positively charged to act as the anode and is submerged in the solution along with negatively charged cathodes. A direct electrical current is then applied to the solution that causes minute fragments of the material to pull away from the workpiece as they are dissolved into the electrolyte solution—leaving behind a clean smoothed surface. Afterward, the parts are subjected to multiple rinsing steps to ensure any residual electrolyte is removed before the parts are dried and shipped out.
3. Top 5 Benefits of Electropolishing
Curious about the benefits of putting your parts through the electropolishing process? Read along below where we break down the top 5 benefits of electropolishing.
- Smoothing effect, good aesthetics.Electropolishing removes high spots on the surface of metal parts. During the process, the dimensions of the lower spots are barely altered, creating a smoothing effect to the base of the metal’s surface. This means that throughout the entire electrochemical process, the total amount of dimensional change needed to obtain the polish effect is very small.
- Easier cleaning and maintenance.Many metal parts and components are used in environments where it is difficult to physically access them for maintenance. Others—as in medical, food and beverage, and semiconductor applications—require repeated sterilization and cleaning. The leveling of micro peaks and valleys through electropolishing not only protects against the “collection” of particulates in otherwise grooved surfaces, but also allows for easier sterilization and maintenance.
- Reduces friction and surface drag, without cracking. A part that has been electropolished properly will experience the performance benefits of reduced friction and surface drag. Visually, the smoothing removes grain boundaries, which significantly reduces the chances of your metal component cracking under stress. In mission-critical applications, you need your parts and components to be operating at their highest level to ensure your business adheres to some of the extremely tight tolerances your end-users require.
- Exposes defective parts.In electropolishing, there is a built-in fail-safe for performing quality control on your parts. Since the process is carried out under the presence of intense chemicals, when a defective part comes through the process line, the chemicals in the electropolishing solution tend to unmask the defect in the part—quickly and obviously. This is a dramatic and effective way of double-checking the quality of your parts being processed before it is sent out to its final destination.
- Corrosion resistance.Free-iron is an almost entirely unavoidable consequence of metal forming in manufacturing. Electropolishing removes metallic and non-metallic inclusions introduced during manufacturing. This results in the removal of elemental iron from the surface of stainless-steel alloys and enhances the chromium/nickel content. The result is a dramatically improved resistance to corrosion. Parts that are professionally electropolished can withstand repeated exposure to water or chemicals and will not compromise the finished surface in medical applications, or in outdoor industrial or architectural installations.
4. NEE’s Electropolishing Services
As one of America’s leading electropolishing companies, New England Electropolishing delivers the highest levels of quality, service and customer satisfaction. Since the early 1980’s we have been driven to exceed customer expectations and are recognized for our ability to achieve quality and consistency, and do what other electropolishing companies cannot.
To give you a broader outline of our capabilities, we’ve broken down our electropolishing services into the following categories based on customer needs and product specifications:
1. Medical Devices:
Our team offers high-level expertise in electropolishing medical devices and assemblies. We tailor our precision processes to meet the unique needs of our valued medical, dental and pharmaceutical customers. We specialize in stainless steel electropolishing, and can finish small components, tools, and tubes consistently with quick turnaround times. Our processes for medical device electropolishing and components are certified to ISO 13485:2016 and 9001:2015 quality standards.
We are experts at electropolishing various types of medical equipment including:
- Surgical devices
- Dental equipment
- Drug dispensing device components
- Arthroscopic, endoscopic and laparoscopic components
- Medical and pharmaceutical equipment
For a more in-depth overview of our electropolishing services for medical devices, visit this page.
2. Small Parts:
All the way back to 1985, NEE has been the business people turn to for the finishing of small components and precision electropolishing. With our rigorous attention to detail, testing, and documented processes, you’re assured consistent and flawless finishes every time. Our small part finishing processes fully comply with ASTM B912,” Standard Specification for Passivation of Stainless Steel Using Electropolishing.”
For more information on our electropolishing services for small parts, visit this page.
3. Large Vessels:
NEE has the capacity to electropolish and passivate your large vessel fabrications up to 8’ long by 4’ in diameter. Any companies doing business in the pharmaceutical, vacuum, marine, architectural and food service industries are welcome to seek out NEE for their large vessel electropolishing needs. Our process fully complies with ASTM B912, “Standard Specification for Passivation of Stainless Steel Using Electropolishing.
For more information on our electropolishing services for large vessels, visit this page.
4. Bulk Parts:
While electropolishing performs best when the work pieces are individually racked, bulk processing has proven to be a cost-effective alternative for some applications. Over the years NEE has developed a proprietary method for electropolishing bulk parts, from screws and bolts to surgical stampings used in invasive procedures.
For more information on our electropolishing services for bulk parts, visit this page.
Do you need help with your next project? Find out how New England Electropolishing can help you with your electropolishing needs. We’ll provide you with our expert analysis, a quote—even a free sample. Contact us now to get a free sample and explore your possibilities!