Environment friendly coatings from Sweden


The new Silver MaxPhase contact coating replaces costly gold plating in production of electrical components

A material that can replace gold on electrical contacts has been developed by Impact Coatings, a Swedish company which traces roots back to the research labs at Linköping University.

Silver MaxPhase™ is a metal alloy that performs like gold in terms of electrical conductivity and resistance to wear and corrosion, but at a fraction of the cost. This offers significant savings and cost control for connectors and other electrical components.

Using Silver MaxPhase is also a substantially better environmental choice than gold plating, as no hazardous chemicals are involved in the process.

“We want to challenge the idea that gold plating is the only option for electrical contacts. An average mobile phone, for instance, has five to 10 connectors that could be coated with Silver MaxPhase,” says chief executive Henrik Ljungcrantz.

The coating is qualified according to the IEC 60512 and IEC 60068 standards for low voltage and low contact force connectors that are normally gold plated, such as battery and I/O connectors for mobile phones.

Silver MaxPhase has the potential to be used for a wide range of connectors and other components.

The metal alloy is applied by physical vapor deposition (PVD), a process that takes place in a vacuum chamber where the material is evaporated and condensed to form a thin film on the object. Impact Coatings has developed the material, as well as processes and machinery for applying the alloy in high-volume production.

PVD is a cost effective, high quality and environment friendly surface treatment. In general, coatings consist of metals or ceramics, usually nitrides, carbides and oxides.The gold replacement coating Silver MaxPhase is applied by physical vapor deposition – for example in machinery for high-capacity reel-to-reel processes

With this highly flexible method, thicknesses of the coatings can be varied from a few atomic layers up to approximately 10μm. A wide range of coating materials and thicknesses means PVD can be custom-made to applications.

The coatings can be optimised for various characteristics such as electrical, mechanical, optical and decorative.

In PVD, the substrate does not need to be metallic or electrically conductive, making it possible to coat non metallic isolators, plastic and ceramic objects.

The possibility of maintaining low process temperatures below 100 degress Celsius further increases the number of applications. PVD is used industrially in a wide spectrum of industrial applications. The most common are semiconductors, CD/DVDmedia, tools, mechanical components, automotive components, sensors, biomedical and optics.

The use of PVD is increasing rapidly in other industries to replace less environmentally-friendly chemical and galvanic methods. Impact’s technology can broaden the use of PVD to even more applications.

Evaporation in PVD can be forced by several methods. The method Impact Coatings most commonly uses is magnetron sputtering, where the coating material is “blasted” from the target by a plasma.

The company offers a range of PVD machinery that can be integrated into existing production flows, with much smaller footprints than a traditional wet plating plant.

The range of machinery includes systems for high-capacity reel-to-reel coating of metal strips, systems for coating of individual metal parts and systems for coating of plastic components.

With significantly reduced environmental impact compared to plating with gold, Silver MaxPhase production lines can be installed without conflict with environmental legislation.