The proliferation of lead-free solder alloys gives users options, but it can be difficult to figure out which of these alloys provides the best match for product requirements. The IPC Solder Products Value Council, in cooperation with iNEMI, offers advice in "Analytical Procedures for Portable Lead-Free Alloy Test Data." The white paper intends to helps users determine which alloy characteristics best match their requirements. It is available as a free download from ipc.org.
After extensive consideration of what physical parameters were most important for reliability, the council's experts determined that solder creep was a key factor that determined many solder qualities.
"If alloys have similar creep values, they are expected to have similar reliability performance over a product's lifetime," said Greg Munie, IPC director of design programs.
In addition, the white paper establishes test protocols for new solder alloys that provide “portable data,” that is, data that is reproducible and not dependent on test location. The protocols formalize testing requirements, reduce the cost of testing and help the industry better understand the basic physics and metallurgy of lead-free alloys in manufacturing and end-use applications.