Avoid Flaking When Plating on Ceramics & Plastics

Plating onto plastics and ceramics can provide a variety of benefits. A coating of gold, silver, nickel or copper will make these somewhat fragile materials stronger and more durable, while increasing their resistance to corrosion as well. The electroplating process can also provide a metallic finish that can enhance a ceramic or plastic product’s visual appeal.

Although plating onto these delicate materials is achievable, the procedure is more challenging than metal-on-metal coating. Many problems can occur that will minimize the quality of the finished product. One of the most common — and preventable — issues is flaking.

What Is Flaking in Plating?

Flaking occurs when the metal does not adhere sufficiently to the surface of a ceramic or plastic substrate. The coating will lift and separate from the surface and peel away, often creating bare spots. Besides leaving the product unprotected, flaking will negatively impact its appearance.

What Causes the Plating on Ceramics and Plastics to Flake?

Flaking can occur for a variety of reasons:

• Inadequate surface preparation: Metal coatings don’t adhere as well to plastics and ceramics as they do to other metals. Thus, proper surface preparation is essential to metalize the material and promote adhesion, which will also minimize the risk of flaking. Surface prep will remove machine oils and other debris and “activate” the substrate. No two plastic or ceramic products are exactly alike, which means the preparation process can vary depending on the material.
• Failure to implement electroless plating: Electroless plating, which applies a metal coating without an electric current, serves as an extension of the surface prep process. An electroplated base coat of nickel or copper can promote adhesion of the top layer and prevent flaking.
• Contaminated plating bath: The failure to monitor the electrolyte solution during plating can allow various contaminants to accumulate. These foreign bodies can obstruct the metal ions and prevent sufficient coating adhesion. Filtering the bath can usually remove many of these materials.
• Excessively thick coating: Some metal finishing companies follow the logic that, because of their comparatively fragile composition, plastic and ceramic materials require a thicker coating to protect them. However, an excessively thick coating can become brittle and eventually “flake off” the product. An experienced plater can determine the appropriate thickness for each material type.

Contact SPC to Learn More

SPC has been developing cutting-edge metal finishing techniques for companies in a wide range of industries for more than 90 years. We can work with you to create a customized ceramic or plastic plating process that will reduce the risk of flaking and improve the quality and durability of your products. Contact us for more information and to receive a no-obligation quote today.