< back to main site

Publications

High-frequency vibration tests of Sn-Pb and lead-free solder joints.

Di Maio, D; Hunt, C (2007) High-frequency vibration tests of Sn-Pb and lead-free solder joints. NPL Report. MAT 2

[img] Text
MAT2.pdf

Download (11MB)

Abstract

The introduction of lead-free alloys, driven by the European legislation Restriction on Harzardous Substances (RoHS), has revolutionised the electronic manufacturing market. 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 the 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 100 Hz, 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 chosen frequencies for this research were 400 and 800 Hz, corresponding to an acceleration in the range of 10 to 20g. The lifetime of the joint was recorded, as well as the material properties’ response to the vibration. This study highlighted the different behaviour of the various alloys when subjected to vibration, and 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, and 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 400 Hz. The method is versatile, and the equipment could easily be modified for testing at high temperatures.

Item Type: Report/Guide (NPL Report)
NPL Report No.: MAT 2
Keywords: lead-free solder, vibration, brittle fracture
Subjects: Advanced Materials
Advanced Materials > Electronics Interconnection
Last Modified: 02 Feb 2018 13:15
URI: http://eprintspublications.npl.co.uk/id/eprint/3979

Actions (login required)

View Item View Item