Wave Soldering Defects


Cracked Joint on a Printed Circuit Board

Cracking of a solder joint on a plated through joint is uncommon; in Figure 1 the solder joint is on a single-sided board. The joint has failed due to expansion and contraction of the lead in the joint. In this case the fault lies with the initial design as the board is not meeting the requirements of its operating environment. Single-sided joints can fail during assembly due to poor handling but in this case the surface of the joint shows stress lines which have been produced during repeated movement.


Figure 1: Crack on a single-sided board was caused by repeated movement during processing
Figure 1: Stress lines here indicate that this crack on a single-sided board was caused by repeated movement during processing.


Figure 2 shows a crack around the base of the fillet and has separated from the copper pad. This is most likely to be related to the basic solderability of the board. Wetting between the solder and the pad surface has not occurred leading to joint failure. Cracking of joints would normally occur due to the thermal expansion of a joint and this would relate to the original design of the product. It is not very common for failures to occur today due to the experience and pre testing conducted by many leading electronics companies.


Figure 2: Lack of wetting between the solder and the pad surface caused this crack at the base of a fillet
Figure 2: Lack of wetting between the solder and the pad surface caused this crack at the base of a fillet.

Celebrating 70 Years of Manufacturing Excellence
America's Oldest. A History of Innovation.

Over the past 70 years, the electronics manufacturing industry has changed dramatically as the industry continues to adapt to evolving demands and technology. Epec is at the forefront of innovation, with the expertise and agility to move at the speed of today’s businesses. At Epec, the customer comes first, and everything we do must be put through that filter. Whether it is developing e-commerce platforms to make it easier to work with us or creating a new product introduction (NPI) process that helps our customers get to market faster, we must focus on building the new. By doing that every day, and by always making the customer our top priority, we plan on being here for another 70 years and then some.

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Celebrating 70 Years - Epec Engineered Technologies