Electroplating is a common manufacturing process that applies a thin metal layer to the surface of another object using an electric current. This coating is applied to enhance the base material’s properties, such as its appearance, corrosion resistance, or durability. Since electroplating is a surface-level application, it does not permanently bond the coating. This layer will inevitably diminish and wear off over time because it is subjected to various physical and chemical stresses.
Mechanisms of Electroplating Wear
The failure of an electroplated surface occurs through three main pathways: physical abrasion, chemical attack, and poor application quality. Abrasion is a purely mechanical process where the plating is physically rubbed away. This is especially evident on items like rings or bracelets that constantly contact skin, clothing, and other hard surfaces, causing the thin metal layer to thin out and eventually disappear.
Chemical attack is a breakdown of the metal layer due to environmental exposure. Substances such as human sweat, perfumes, lotions, household cleaners, and chlorine contain chemicals that react with and dissolve the metal plating. This process causes discoloration or tarnish, compromising the integrity of the coating until the base material is exposed. When the base metal is exposed, corrosion can accelerate further if the exposed metals react poorly together.
Poor adhesion relates to the initial quality of the application. If the substrate was not properly cleaned or prepared before plating, the coating will not bond correctly. This poor bond can lead to the plating flaking or peeling off in sheets rather than gradually wearing away. Proper surface preparation ensures the coating adheres tightly, preventing premature failure.
Factors Governing Plating Lifespan
The single most important factor governing lifespan is the plating thickness, which is measured in microns. A thicker layer inherently provides a longer-lasting barrier against wear and corrosion. For example, decorative gold plating on consumer goods might range from 0.1 to 0.5 microns, while a functional coating can be several times thicker, directly translating to a greater lifespan.
The type of plating metal also plays a significant role in determining durability. Harder metals such as chromium or rhodium offer superior resistance to wear and friction compared to softer metals like pure gold or silver. The choice of metal is often a trade-off between the desired aesthetic or electrical property and the required mechanical strength.
The base material also influences the lifespan, particularly when the plating is compromised. If the plating wears through, exposing a base metal like copper or brass, the exposed material can quickly tarnish or corrode. This rapid tarnish can undermine the remaining plating around the exposed area, accelerating the overall degradation of the finish.
Finally, the environmental exposure of the item heavily impacts its longevity. Constant humidity, temperature fluctuations, or corrosive environments speed up the degradation process.
Practical Steps for Preventing Wear
Extending the life of electroplated items requires careful handling and maintenance to minimize abrasion and chemical exposure. Avoid contact with common household and personal care products that can strip the finish. This includes alcohol-based hand sanitizers, harsh cleaning agents, hairsprays, and perfumes, which contain ingredients that chemically attack the thin metal layer.
When wearing jewelry, put it on last after applying cosmetics, and take it off first before washing or exercising. Sweat is mildly acidic and can hasten the breakdown of the plating, while chlorine in pools and hot tubs is particularly damaging. Removing plated items before activities that cause heavy perspiration or water exposure will significantly preserve their finish.
Proper storage helps prevent wear by limiting physical damage and exposure to moisture. Items should be kept dry and stored separately in soft pouches or small compartments to prevent them from rubbing against each other. For cleaning, use only a soft, dry microfiber cloth or a mild soap and water solution to gently remove oils and dirt. Abrasive cloths or harsh scrubbing tools should always be avoided as they physically remove the plating layer.
Options for Restoring Worn Plating
Once the electroplating has worn away and the underlying base metal is visible, the item can be restored through professional re-plating. This process involves thoroughly cleaning the item, sometimes chemically stripping any remaining old plating, and then submerging it into a new electrolytic solution. Professional services can apply a new layer that is of a higher quality and thickness than the original finish.
For small areas of wear, particularly on non-jewelry items, specialized DIY repair kits are available, frequently using a technique called brush plating. This method uses a small, absorbent material soaked in plating solution and attached to an electrode to apply a localized coat of metal. While convenient for small touch-ups, these home kits yield a less durable or uniform result compared to the precise control of a professional immersion tank process.