Working temperatures influence over the solder joints properties

It is an actual trend for electronic equipment to be used into growing range of working temperatures and at high level of the mechanical stress. As example, for the domains exempted by RoHS 2 EU Directive (it became law from January 2013) like aerospace, the standard maximum working temperature is 398.15K (125°C). The results of the comparative investigations regarding electrical and mechanical properties of the Lead/Lead-free solder joints function of working temperature and soldering thermal profile are presented in the paper. The experiments were designed based on previous work [1,2] having as starting point the “Homologous Temperature” concept [1,3,4], in order to respond to constrains imposed by the qualification processes of lead-free solder alloys for usage into exempted domains according to the RoHS 2 EU Directive [5,6].