Whether electronic circuits or connector parts, quality controls must be carried out throughout the production process. In general, the priorities are to check brazing, electrical contacts between the various components and the printed circuit board, metallisation quality, dimensional characteristics, coating thickness, etc.
The main materials found in the field of electronics are:
• Metals with excellent electrical conductivity or coatings such as copper, silver, nickel and gold,
• Tin alloys for soldering,
• Polymers for printed circuit boards and electronic modules,
• The glass and ceramics (and silicon) that make up the various components.
Inspection requires metallographic preparation. Obtaining an inspection surface requires a succession of operations, each as important as the next, regardless of the material.
These steps are in the following order:
• The removal of the product to be examined (if necessary), called “CUTTING”.
• Standardisation of the geometry of the sample taken (if necessary), called “MOUNTING”.
• Improvement of the surface condition of this sample, called “POLISHING”.
• Characterisation of the sample: revealing the microstructure of the sample by an etching reagent (if necessary) called “METALLOGRAPHIC ETCHING” and microscopic observation (optical or electronic).