Plating on Plastics
Modern engineered plastics are used in countless industries and applications throughout the world. These materials are popular for many reasons, including their versatility, easy machinability, and excellent surface finishes. However, because plastics are not electrically conductive, they are very difficult to plate with proper adhesion. Our electroplating projects have been described as having “excellent adhesion and RF performance” by our clients. This is important because many of the applications for plastic plating will be deployed in extreme environmental conditions, such as high temperature or high altitude/low temperature ranges.
What is Plastic Electroplating?
Electroplating is the process in which dissolved ions of one metal are deposited onto the surface of another metal. Plastic plating is commonly used in many industries for purposes such as corrosion and wear protection, increasing surface hardness, promoting electrical conductivity, or for improving the appearance of a part or component. The process of plating metal onto plastic is now a widely accepted industrial practice that offers several crucial benefits for manufacturers everywhere.
The Electroplating Process
Surface preparation is critical in obtaining sufficient adhesion of the desired metallic coating. ENS uses a mechanical ablating electroless process to microscopically enhance the anchor points on plastic substrates.
To provide a workable surface area, the material being treated is chemically cleaned and the exposed areas are stripped of surface contaminants in a series of closely monitored chemical baths. The workpiece is then autocatalyzed with high purity noble metals, culminating with the last autocatalytic layer of Electroless Copper. Then, a layer of pure electrolytic copper metal is deposited across the exposed surface(s) of the plastic workpiece. Depending upon the form, fit and function of the part, Electrolytic Copper can be the final metallic layer, or the under-plating for additional metals.
Once the plastic has been metalized with electroless copper, it can then be further processed as if it were a metallic, conductive substrate. ENS can then deposit additional electrolytic platings onto the coated plastic, such as:
Depending on the material, a thin layer of autocatalytic nickel can be deposited to provide a solder barrier solderability.
In many plastic plating applications, it is necessary to apply an undercoat onto the plastic substrate prior to electroplating to build thickness and promote proper bonding of the coating. A process known as electroless plating is typically used to accomplish the task. Electroless plating differs from electroplating in that no electrical current is used to deposit the coating. Instead, deposition occurs via an autocatalytic chemical reaction. Nickel and copper are the two most frequently used metals for electroless plating, although techniques for gold and tin have also been established.
Types of Plastic Plating Materials
ENS Technology is one of few plating providers with the capabilities to plate plastics with superior adhesion. Many of these materials are classified as thermoplastics, which means they become moldable when heated above a certain temperature, and then they solidify upon cooling. Using our special, multi-step process, we can apply metal plating to:
- Teflon®, PTFE, PFA,
- Torlon®, PAI
- SLA resin
- and other plastics
Electroplating provides the ability for a non-conductive plastic surface to conduct electricity. This has provided manufacturers of electronic parts and components used in automobiles, aircraft and a multitude of other products the ability to build lighter products that still conduct electricity. A metal coating can also reflect potentially destructive light away from the surface of a plastic substrate and serve as a defensive barrier against detrimental gases and corrosion. Additionally, metallization can assist in controlling the dissipation of energy.
Electroplating plastic parts is also used to protect the plastic from manufacturing chemicals that could potentially damage the plastic. It is also a great way to protect a plastic part from corrosion. The plating process will also increase the wear resistance and strength of the product.
In addition, electroplating enhances the appearance of the material and generates the impression of increased quality. As a result, it is often selected when an enhanced look is desired.
There are several industries that use plastic plating on a regular basis to provide beneficial qualities to their plastic parts, some of which include:
The automotive industry is the principal leader in usage of plastic on plating technology. They occupy around 80% of the market share of electroplate usage. The ability to mold and bend plastic into just about any shape gives engineers a broader range of options when developing vehicle styles that differentiate their company’s products from those of the competition. Producers of OEM and aftermarket parts are also making extensive use of plastic plating.
Plastic plumbing fixtures are now regularly used within the industry due to cost savings over varying metal options. However, plastic is not always the most aesthetically pleasing material to have within a home, so plastic plating is often used to enhance the appeal of the plastic fixtures.
Plastic plating is regularly used in the construction of electronic components and accessories. Nickel and nickel-chromium plating is used to enhance the appearance of the plastic trim on computers and mobile phones, as well as the various control knobs, switched and buttons on a wide range of home electronics and electrical appliances.
The History of Plastic Plating
Electroplating on plastic first gained notoriety within the auto industry in the 1960’s. Automobile manufacturers were seeking ways to make their vehicles more fuel efficient, which led to the increased use of lightweight plastic parts and components. Electroplating served the purpose of “metallizing” these parts to give them the gleaming appearance that appealed to most car buyers of the era. A key advancement was the development of a reliable chemical process for the surface preparation of acrylonitrile butadiene styrene (ABS), a thermoplastic polymer that offers the toughness and impact resistance required for automotive manufacturing applications. The new process provided sufficient adhesion between the ABS substrate and the metal coating. Electroplating within the automotive industry is still used to this day.
Contact ENS Technologies Today
ENS Technology is an industry leader in the metallic plating of plastics. Contact us today to learn more or to start your project.