Contact surfaces - Delivering strong performance with less gold

The design of PCB connectors is often based on reaching the best possible compromise between technical and economic requirements. On the technical side, factors such as the mechanical load capacity of the connection, the specific environmental conditions during operation, and the concrete specification of the transmission power to be provided must be taken into account. From a cost-effectiveness point of view, manufacturers needs to ask themselves how high the quality of the product really needs to be, factoring in the purpose and duration of the application.

It often seems that customers are acting on autopilot when they specify goal-coated plating – especially for high-quality and technically demanding products. But in fact, gold is the only material that optimally combines all the properties that make up the quality of a connector: Gold is resistant to corrosion and withstands the harshest environmental conditions, shows hardly any material fatigue even after a large number of mating cycles, and ensures optimum transmission of current and voltage even at temperatures as low as 150 degrees Celsius. Depending on the application, silver is traditionally used as the more cost-effective alternative coating, and it also performs even better than gold in terms of electrical conductivity. However, the significantly higher contact normal force can lead to unwanted restrictions being placed on the design of the connector in individual cases.

By continuously optimizing the production process, an inhouse strip plating line not only allows manufacturers to process a wide range of contact types, but also enables them to realize specific custom plating in a way that is cost-effective. As far as the use of gold is concerned, it is possible for a connector manufacturer with its own inhouse electroplating line to reduce the amount of valuable precious metals it uses to an absolute minimum by, for example, only selectively coating contacts of male and female connectors directly at the point of actual current and voltage transfer. In addition, an inhouse electroplating line offers connector manufacturers the advantage of being able to realize a variety of other material combinations, such as nickel, tin, tin/lead, nickel/phosphorus and palladium. 
We recommend choosing a connector manufacturer with its own electroplating line if you want to benefit from an optimal cost-benefit ratio and ensure maximum flexibility in the plating and the coatings you need configured. As one of the world’s leading manufacturers of PCB connectors, ept GmbH operates six of its own strip electroplating lines at two German locations, enabling the production of coatings from a maximum of ten different surface combinations with a minimum of modifications. 

 All of this does not mean that the customer- and application-specific configuration of PCB connectors is limited to the surface – it encompasses the entire structure of a contact, including its base material and intermediate layer, too. Special processes that are developed based on the respective technical and economic requirements allow fully customized products to be manufactured, the quality of which is verified by continuous testing in our inhouse laboratories. In this way, operation in accordance with specifications is tested under conditions that far exceed the relevant standards. An example of this are the requirements according to DIN 41612 connectors, according to which the quality of a product must be completely guaranteed even after 500 (performance level 1) or 400 (performance level 2) mating cycles.