Product category:
Recruitment, Reports and Resources
News Release from: National Physical Laboratory
Edited by the Electronicstalk Editorial
Team on 19 September 2007
Report details solder joint vibration
resistance
Lab publishes findings of vibration tests on lead-free solder alloys, using traditional SnPb alloy as a benchmark.
The UK's National Physical Laboratory has released a report detailing its work conducting high-frequency tests of lead-free solder alloys, using a reproducible model solder joint as the sample, to which well controlled vibration has been applied The chosen frequencies for this research were 400 and 800Hz, corresponding to acceleration in the range of 10 to 20g
This article was originally published on Electronicstalk on 6 Apr 2005 at 8.00am (UK)
Related stories
Scanning acoustic microscopy spots reflow damage
The NPL has developed broad expertise in applying scanning acoustic microscopy for assessing the level of delamination in printed circuit boards and die cracking inside electronic packages.
Calibration service assures coax connector specs
The 7-16 precision coaxial connector was developed during the 1960s during an era when such connectors were beginning to become standardised.
The study highlighted the different behaviour of the various alloys when subjected to vibration, in particular the superiority of the SnPb alloy, especially at higher frequencies.
This method has been shown to be useful in characterising and ranking various materials, tests could be easily repeated with a range of conditions, targeted at specific industrial applications.
The results suggest that the higher the concentration of silver in the lead-free alloys, the better is the performance at 400Hz.
The method is versatile, and the equipment could easily be modified for testing at high temperatures.
With the introduction of lead-free alloys, driven by the European RoHS legislation, the electronic manufacturing industry has been revolutionised.
New materials have replaced conventional SnPb alloy in a large number of applications and many more will follow.
For this reason a better understanding of the properties of new solder alloys in a broader range of applications is clearly needed.
There are many applications in which electronics devices are subjected to vibration.
Yet while there has been much research into the effects of low-cycle fatigue, there has been very little in the field of high-cycle fatigue, despite this being of interest in critical fields such as the aerospace industry.
In consequence, this work has been aimed at studying lead-free solder alloys in a high frequency environment, above 100Hz, using SnPb alloy as a benchmark.
Many previous studies on high-cycle fatigue have been focused on studying the effects on a full printed circuit board.
That assessment method, however, is not suitable for characterising the solder performance, as the approach is geometry and condition specific.
In this work therefore, a more general approach has been adopted, using a reproducible model solder joint as the sample to which well controlled vibrations have been applied.
The lifetime of the joint was recorded, as well as the material properties' response to the vibration.
• National Physical Laboratory: contact details and other news
• Email this article to a colleague
• Register for the free Electronicstalk email newsletter
• Electronicstalk Home Page
Search the Pro-Talk network of sites
