Why Gold Plating PCBs Are a Good Idea
Gold plated PCBs provide outstanding durability against corrosion, heat and other environmental stresses. They’re also good at transferring electrical currents and can be alloyed with cobalt and nickel to improve wear resistance.
Hard gold has a precise grain structure and a dazzling appearance. It is ideal for applications requiring visually acceptable gold contacts such as visible interconnects.
Conductivity
Gold has excellent conductivity, which makes it a popular choice for PCB contacts. It is also resistant to corrosion and oxidation, making it less susceptible to damage. It also has a strong tolerance for heat. This is a useful feature for printed circuit boards that need to be exposed to high temperatures.
A common way to protect a copper contact on a circuit board is to use an immersion gold coating. This is a type of gold surface treatment that involves immersing the copper parts in an electrolyte. The coating then bonds to the underlying metal. It can be applied to the entire surface of the circuit board, or it can be selectively applied to specific areas.
Selective gold plating is another option for PCB contacts. This process uses a low-viscosity ink that is deposited over the contact area. This ink is then cured with thermal curing, gold plating pcb which creates a smooth, conductive film. It is an efficient alternative to traditional methods for repairing copper contact points.
When using gold-plated PCBs, it is important to keep the inner layers free of copper. This will prevent the copper from diffusing into the gold during the beveling process. It is also a good idea to keep a distance of at least 1 mm between the gold fingers and any Plated Holes. This will ensure that the solder mask and silk screen printing are not damaged during beveling.
Durability
Gold is a very durable material that does not oxidize easily. This makes it a great option for PCBs that need to be used in harsh environments, such as those that must be exposed to water or air. This durability is important, as it will help ensure that the circuit board can function properly for a longer period of time. In addition, it will also reduce the need for frequent maintenance.
The most common type of gold plating for PCBs is immersion gold. This type of gold coating is very thin and is deposited on the nickel surface of the copper-clad laminate. It is not as durable as other types of gold plating, but it still provides good electrical conductivity. This is why many manufacturers choose to use it.
Another advantage of gold plating for PCBs is that it is not susceptible to fretting degradation. Fretting corrosion occurs when two surfaces are touching and rubbing together. This can cause small oscillatory movements, which can lead to material deterioration over long periods of time. Gold is not affected by this phenomenon, making it a more durable option than other materials.
However, it is important to note that even hard gold can corrode over time, especially if it is not protected by a nickel underlayer. This is why it is important to use the right coating thickness. A thin layer will cause the PCB to oxidize and fail, while a thicker layer will protect it from oxidation.
Ductility
Gold plating on the edges of a PCB is a way to increase the durability and longevity of your products. It also helps protect against oxidation, which is common in most applications that require a lot of friction. In this case, it is important to ensure that the plating process is done properly to avoid oxidation and pad blackening. If the process is not done correctly, it can result in huge losses for the company.
A conductive layer of nickel under the hard gold plate is crucial for PCBs that need to resist corrosion. The nickel underplating obstructs the pores of the gold and prevents them from getting filled with copper oxide. It also acts as a diffusion barrier, which helps prevent the formation of poorly bonded intermetallic layers and corrosion.
Hard gold can withstand higher contact pressure and sliding wear than Gold Plating PCB Supplier ENIG plating, but it is still not as durable as tin. However, it is much easier to solder and bond with than tin.
In addition to its hardness, hard gold is also more resistant to fretting degradation than copper. Fretting corrosion is a type of material deterioration that occurs when two contacting surfaces make small oscillatory movements over extended periods of time. This phenomenon is exacerbated in harsh environments and is difficult to detect with a naked eye.
Stability
Gold is an excellent material for PCBs, as it offers exceptional conductivity and resistance to corrosion. But it is not durable on its own, so it is best plated above a hard material such as nickel or cobalt. The process of laying gold on a circuit board begins with pre-treatment and cleaning with etchants and conditioners. After that, the board is activated with a catalyst and lowered into a metal ion bath. Gold deposits of varying thicknesses are deposited on the surface. The thicker coatings are more resistant to wear.
Hard gold plating is a great choice for military applications, as it can resist extreme temperatures, humidity, salt, and radiation. It also has better strength and rust resistance than traditional copper boards. It is also easy to solder, making it ideal for high-speed connections. However, it is important to note that excessive cleaning wears down the gold plating, so you should avoid using abrasive cleaners on your circuit boards.
Another benefit of hard gold plating is that it offers higher conductivity and lower contact resistance. This makes it an excellent option for high-speed applications, such as data transmission and signal integrity. It is also a good choice for long-term use, as it is less prone to short-circuiting than nickel-plated gold.