A crucial design aspect for connection and contact applications is the proper specification of gold plating thickness. Gold plating is an excellent finish for connections that require high reliability and durability; nevertheless, the thickness of the gold plating has an impact on the connector’s overall durability and life cycle. Gold plated connectors have a low contact resistance, making them ideal for applications that require low signal voltages and currents in the millivolt and milliamp range.
Determining the proper thickness for gold plating connectors and contacts may be tricky. Connectors must function reliably even in extreme situations, and they can only do so if the plating is well constructed and has the appropriate thickness. Furthermore, because gold is a costly material to obtain, it’s critical to only make plating as thick as it needs to be – any plating that is thicker than necessary is a waste of money. Because gold is a noble metal that does not readily react with chemicals in most settings, gold plated connections will maintain their conductivity over time as long as the gold thickness provides a suitable barrier to the substrate from the environment.
Gold plating of connectors is often coated in very thin layers of 5uin to 100uin (0.1um-25um) in comparison to other plated metals due to the expensive cost of the precious metal. In extreme instances, however, gold can be plated to thicknesses of 500uin to 1000uin (12.5um to 25um). The corrosion and wear resistance of the gold plated connector rises as the thickness of the gold grows.
When an extremely thin “flash” gold deposit (less than 10uin, 0.25um) is applied on connectors, the gold becomes exceedingly porous. Although the gold plating thickness appears to be continuous, the deposit contains thousands of small pores, making it more like a thin gold screen than a continuous pore-free coating. Although gold plating may not quickly react to corrosive conditions, the holes in the gold allow the substrate to oxidise and erode through the gold.
The thickness of a gold connector can be increased to improve corrosion resistance and wear resistance. The pores in the deposit shrink in size and quantity as the gold plating thickness increases. As the thickness of the gold plating increases, the pores will eventually shut completely, resulting in a pore-free gold layer. When gold plating is entirely pore-free, it provides excellent corrosion barrier protection, keeping the material from corroding. However, due to the high cost of gold, it’s critical to strike a balance between the plating’s functional needs and the stipulated gold thickness to create the most cost-effective gold plated connector or contact.
Thin Gold Plated Connectors
The typical gold plating thickness for gold connectors used in a controlled environment with minimal wear considerations is 4-20uin (0.1-0.5um). This spectrum of thin gold layers can give low contact resistance, great solderability, and wire bonding while using very little gold. For static gold contacts that do not cycle or slide during use, this is a common thickness. Grounding nuts or studs, fixed contacts, and solder pads are all examples.
Moderate Thickness Gold Plated Connectors
Common functional gold plating thickness is from 30-50uin for connectors and contacts with moderate ambient and wears cycles (0.75-1.25um). When compared to thin gold or gold flash plating, this amount of gold thickness gives much-improved corrosion resistance. Furthermore, for dynamic connectors or contacts that cycle during usage, thicknesses in this range provide moderate to good wear resistance.
Although gold plating is not normally pore-free at these modest levels, the thickness of the gold is sufficient to give some corrosion protection in mild settings without multiple condensation cycles or the risk of corrosive chemical assault. Components plated in this thickness range include male/female pins/sockets, phosphor bronze or beryllium copper flex contacts, and gold plated contact springs.
High Thickness Gold Plated Connectors
For applications requiring the best corrosion protection and wear resistance, heavier gold deposits of 50uin (1.25um) or more are frequently required. To generate a totally pore-free layer that will give the best barrier protection against corrosion of the base material, 100uin (2.5um) or more of gold plating is necessary, depending on the base material and surface polish of the connector.
Mil-spec and Oil & Gas connection applications that are exposed to more severe conditions, as well as heating and switching cycles, commonly use gold plating of contacts or connectors more than 50uin. Heavier gold deposits in this range, when properly developed with the proper underplate, provide enough material to allow for very high cycle applications of 10,000 cycles or more.
Gold provides a number of advantages when plated on connectors and contacts, including low contact resistance, long-term conductivity stability, corrosion resistance, and solderability. The thickness of the gold plating is an important design factor since it affects the gold deposit’s characteristics and endurance. It’s critical to get the gold plating thickness just right. When it comes to choosing the proper gold plating, thickness is only one factor to consider. As a result, be certain that all of the other factors are in order.
Smart Microns in Chennai offers gold plating services. Smartmicrons services provide hassle-free plating and delivery of restored objects because of our team of experts who cherish quality. We are a global pioneer in 24kt gold plating and deliver cost-effective and durable metal plating and coatings for a variety of industrial and commercial applications.