Component failure

What is it?

Exposure of many traditional components to the higher temperatures required for Lead-Free assembly can result in catastrophic failures, degradation of performance parameters or shortening of functional lifetimes.

Why does it happen?

During routine Lead-Free soldering operations on standard assemblies components may be exposed to temperatures of over 240°C whilst, in some more difficult soldering operations on thick high thermal mass boards with a large component counts, temperatures of up to 260°C may be required.

Also, for mixed technology boards, there may be a need to expose components to multiple soldering cycles, thus exposing components to higher temperatures a number of times.

What problems can it cause?

High soldering temperatures may lead to a number of different failure mechanisms. The basis of the problem is that many of the materials used in electronic components are organic and are susceptible to high temperature exposure. The higher the temperature and the longer the exposure time, the more likelihood there is that there will be damage.

There have been reports of aluminium electrolytic capacitors being destroyed during Lead-Free soldering and also of the light outputs of light emitting diodes being degraded by exposure to higher temperatures. In addition to the immediate effects of exposure to high temperatures, there are also concerns about impacts on the long term life and reliability of components.

How can it be prevented?