COST531: Lead-free Solder Materials

Owing to impending European legislation, lead will no longer be used in the fabrication of electrical and electronic materials within Europe. COST 531 was a European action on the study of new lead-free materials suitable for use in the electronics industry and ran from March 2002 to March 2007. Its basic remit was "to increase the basic knowledge on possible alloy systems that can be used as lead-free solder materials and to provide a scientific basis for a decision which of these materials to use for different soldering purposes in order to replace the currently used lead-containing solders in the future".

45 research institutes from 17 countries took part on the project representing very successful collaboration across Europe and with cooperating countries. There were six working groups:

• Groups 1&2: Thermochemistry and Phase Diagrams (Experimental + Modelling)
• Groups 3-6: Physical, Chemical Properties, Reliability Issues

Outputs from the Action include:

• Thermodynamic database: Ag, Au, Bi, Cu, In, Ni, Pb, Pd, Sb, Sn, Zn
• Database of Physical Properties of Lead-free Solder Alloys physical and mechanical properties of bulk solders and solder joints
• SURDAT Database of Lead-free Soldering Materials
• ATLAS of Microstructures of Pb-free solders and solder joints
• Synt@all” (SYNthesis of ALLoys)
• COST 531 Atlas of Phase Diagrams
• COST 531/ELFNET Handbook of Solder Alloy Properties

What is COST ?

Further information about COST531.