Dynamic EMS Tackles the Subject of Surface Tension – Friend or Foe

Dynamic EMS Tackles the Subject of Surface Tension – Friend or Foe

By Andy Hutchison

 In this series of blogs, we look at some of the questions that are often asked by customers, dispel some of the myths about the electronics manufacturing industry, and provide examples of how experienced staff can resolve issues in manufacturing.

This blog will look at surface tension and some of the challenges we face as manufacturers.

We are all familiar with surface tension on water, the water molecules are electrostatically attracted to each other (hydrogen bonds), however at the interface between the surface water and air, the water molecules have a much stronger attraction to each other than to the air molecules, therefore the imbalanced forces of the water molecules are redistributed towards the adjacent surface water molecules making a stronger bond at the surface (surface tension).

This surface bonding forms an elastic skin, this is how pond skaters can stay on the surface of water, how water droplets form a ball and more importantly how solder joints get their unique shape.

Surface tension can be a friend, we are familiar with self-alignment where components placed offset realign during soldering, and it’s also the surface tension that forms through-hole solder joints in wave and hand solder.

In surface mount soldering surface tension is a powerful force it causes solder float, pulling and pushing out of alignment, tombstoning, or tilting, sometimes these can be overcome with process changes, however design issues become a little more complex.

At Dynamic EMS we use our understanding of the surface tension forces to overcome some design issues due to solder float, or tombstoning, and poor alignment.

About Dynamic EMS

At Dynamic EMS, we understand that no two-electronic equipment manufacturing customers are the same.  Their products, their supply chains, and their markets all differ, which is why Dynamic EMS offers tailor-made, customised electronics manufacturing services to customers with complex, highly diversified business.

From design to distribution, we enable our customers to be more competitive by bringing innovative solutions to market faster, with a commitment to quality in everything we do.  Dynamic EMS – Your Product Solutions Architect.

Enabling Market Solutions for all technology companies.

Find out more about Dynamic, www.dynamic-ems.com.

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