Wave Soldering Defects


Flux Residues on a Printed Circuit Board

Flux residues visible on the board are more common due to the reduction in the use of cleaning in the industry. Over 75% of companies in Europe use no clean low residue materials. With the reliability of no clean being demonstrated in automotive products, the number of cleaning processes will continue to decline.

In Figure 1, the residues are either a result of the formulation of the flux or due to poor process conditions. Many no clean materials rely on the correct pre-heat temperature helping to minimize the residues left on the board. Wave contact time may also affect the residues left on the board. Discussion with the flux supplier should provide the correct process parameters.


Figure 1: The flux residues here could have been caused by the formulation of the flux or by poor process conditions
Figure 1: The flux residues here could have been caused by the formulation of the flux or by poor process conditions.

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As the oldest production Printed Circuit Board Company in North America, perhaps in the world, the 60-year plus story of Epec is connected to the development of the PCB and the electronics industry.

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  • Epec Founded in 1952
  • IPC Founded in 1957
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