Plating is a protective coating. Proper selection is based on the application which will also dictate thickness requirements. The common thickness used in industry today are as follows:
|Gold, Hard:||50 microinch — military, process control, medical, high reliability systems.
30 microinch — general industrial applications.
20 microinch — short life
< 10 microinch — limited to application specific areas, very restrictive use. May be enhanced with lubricants or surface conditioners.
|Tin (alloys)||100 microinch - Minimum recommended.|
|Gold Flash Pd Ni||> 30 microinch (if the gold flash remains)|
The following tables summarize the use of various plating systems in a variety of applications. The class definitions are in two categories, general and application specific. The second table is a rating based on field and/or test data accumulated over time.
There are other failure mechanisms that are prevalent in connectors, such as:
- Fretting Corrosion
- Stress Relaxation
- Data Bit Loss
- Plastic Degradation Mechanisms
- Signal Integrity Issues
Although plating selection plays a part in those issues, there are other factors and dynamics which tend to dominate and thus are beyond the scope of this work.