Corrosion Resistance

Electropolishing: The Advanced Alternative to Passivation

Electropolishing is increasingly recognized for its superior ability to enhance corrosion resistance across a wide range of metal alloys. While it is most commonly applied to stainless steel, electropolishing is equally effective on other metals. Thanks to its versatility and superior performance, electropolishing is rapidly emerging as a preferred alternative to traditional passivation processes.

Limitations of Traditional Passivation

Passivation is a long-established chemical process designed to remove free iron and surface contaminants from stainless steel, creating a chromium-rich layer that enhances corrosion resistance. Engineers often specify passivation due to the many potential sources of contamination during manufacturing and handling. However, passivation has its limitations. It is generally ineffective in removing embedded free iron, oxide scale, or heat tint—particularly on welded, brazed, or heavily machined components. As a result, it may fall short in meeting the strict standards of salt spray and humidity testing required in many high-performance applications.

Why Electropolishing Outperforms Passivation

Electropolishing works by selectively removing the outer layer of metal, effectively eliminating deeply embedded contaminants that passivation cannot reach. This makes it ideal for complex components such as machined parts and welded assemblies that typically do not respond well to passivation alone.

Unlike passivation, electropolishing can be used on all stainless steel grades—including 400 series and precipitation-hardened alloys—without risk of distortion, hydrogen embrittlement, or flash attack. The process not only passivates the material but also significantly improves surface finish and corrosion resistance.

Dual Benefits: Electropolishing + Passivation

Every part that undergoes electropolishing is inherently passivated during the process. Moreover, electropolishing enhances corrosion resistance on a variety of metals, including stainless steel, copper, brass, aluminum, and carbon steel. By removing the surface layer and embedded impurities, the process improves the overall durability and longevity of the component. For example, the parts shown (right) are made from Type 303 stainless steel and underwent multiple machining operations. These operations introduced surface contamination that required complete decontamination. Under 40X magnification via scanning electron microscope, the difference is clear: the passivated surface appears rough due to chemical attack on the sulfur-rich 303 alloy, whereas the electropolished surface is noticeably smoother and cleaner. This is because electropolishing precisely dissolves the surface skin, along with embedded steel particles and other contaminants, ensuring a cleaner, more corrosion-resistant finish.
Medical Device Manufacturing

From implantable devices to surgical instruments, electropolishing provides a single-step treatment that delivers biocompatible, ultra-clean, and safe components.

Aerospace

We provide aerospace vendors and OEMs with our signature metal finishing services, enhancing fatigue resistance and ensuring their metal parts withstand long-term stress and corrosion.

Pharmaceutical

We follow industry standards to electropolish pharmaceutical components in compliance with ASTM B912 and ASME BPE, ensuring clean, smooth, corrosion-resistant surfaces free from contaminants.

Automotive

Corrosion resistance and micro finish improvement are essential for critical automotive parts, making electropolishing an increasingly beneficial option for automakers.

Consumer Appliance

Our metal finishing services enhance corrosion resistance and, through electropolishing, remove the outermost metal layer boosting the durability and lifespan of appliance components.

Food & Beverage

Electropolishing materials used in this industry help prevent bacterial biofilm buildup and eliminate contaminants like Salmonella. This process ensures the high level of sanitation required by various regulatory agencies.

Hydraulics & Pneumatics

From robotics to mobile equipment, electropolishing plays a vital role in the hydraulics and pneumatics industry. By preventing premature part failure, it minimizes downtime and extends the lifespan of critical components.

Electronics

Electropolishing enhances both conductivity and performance in electronic components. It also improves surface finish by up to 50%, eliminating imperfections without compromising the material’s integrity.

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