1 Introduction
In the connector PCB plating , because exposure to have higher electrical performance requirements , gold plating process occupies an important position in the connector obvious PCB plating . Present, except for portions of the strip connector PCB selective gold plating process , the remaining a large number of pinholes hole parts still use gold-plated barrel and vibration plate to recent years, the development of more compact connectors volume , and its gold-plated hole pinhole parts quality problems have become more prominent, the user gold layer on increasingly high quality requirements , some users on the quality of the gold layer appearance and even reached a very critical level. connector gold layer in order to ensure the quality of the binding force of these types of common quality problems always improve quality gold-plated connectors the key reason for these quality problems below were provided by one of our discussion boards .
2 , the gold layer causes of quality problems
2.1 gold layer color is not normal
Colour gold layer with a normal connector inconsistent gold layer , a gold layer or a different part of the same color appears differentially related products , there is a reason for this problem :
2.1.1 gilded raw material impurities affect
When added to the bath degree endure chemical materials into liquid impurities than gilded gold layer will soon affect the color and brightness. If organic impurities affect the gold layer will appear dark and blur phenomenon, Hao Er tank test ray examination and dark blur position is not fixed. metallic impurities interference if the current density will result in the effective range narrows, Hao Er cell test specimen display is not lit or low end of the current density plating is not on the low end of the high-end non-galvanized reflecting on the plating is a coating redness or even black, the color of the more obvious changes in their holes .
2.1.1 gilded current density is too large
Since the total area of the plating tank parts miscalculation its value is greater than the actual surface area , so that the current is too large gilded or gold plating PCB model using vibration amplitude when it is too small, so that all or part of the tank plating gold plating crystalline rough mesh depending on the gold layer redness.
2.1.3 plating solution aging
Plating solution is to use the bath for too long will inevitably result in excessive accumulation of impurities in the gold layer color is not normal .
Not on the gold -plated 2.2 hole
After the connector pin or socket plating process to complete the outer surface of the plating thickness reaches or exceeds the specified thickness , its wire jack bore holes or thin or no gold plating layer .
2.2.1 plating gold-plated plug for each other
In order to ensure the connector jack plug socket to use when having a degree of flexibility in product design most kinds of PCB jack there is a split mouth design PCB slot in the PCB electroplating process plating continue turning part of the jack plug on each other in the opening part of the power cord plugged led to another hole PCB plating shielding caused difficulties .
2.2.2 gilt plating end to end
Some types of connector pins in the PCB design of its diameter size of its needle bar is slightly less than the pore size wire holes in the PCB electroplating process will form part of the pin hole plated wire end to end without result into gold . these two phenomena in the gilded more prone to vibration .
2.2.3 Blind site concentration greater than PCB electroplating process covering power
Since the split in the bottom of the jack slot is still some distance away from the bottom of the hole , the distance on some objective form of blind holes. Similarly pin hole in the wire and jacks where there is such a blind hole , which is to provide wire bonding when guiding role when the aperture smaller holes and blind holes these concentrations exceed the aperture when the bath is difficult to flow into the hole, flowing into the hole out of the bath and very difficult , so the gold layer is difficult to guarantee the quality of the hole .
2.2.4 gilded anode area is too small
When the connector is relatively smaller total surface area when plated on large single-slot , so that when a small pinhole -plated pieces if Single plating more . Original anode area becomes insufficient , especially when platinum titanium mesh when you use too much for too long platinum loss , will reduce the effective area of the anode , which would affect the gilded throwing power , plating plated hole will not enter .
