The graphic below shows the stress-strain curves and BGA sphere fracture areas generated by shear impact tests with speeds of (a) 100 mm/sec and (b) 1000 mm/sec on an electroless Ni/Immersion Au surface finish. (The fracture areas are compared to Sn-37Pb normalized to 100 percent).
The fracture area of SN100C is similar to that of Sn-37Pb at the shear speed of 100mm/sec but the fracture area for Sn-3.0Ag-0.5Cu is smaller than Sn-37Pb.
The fracture area of SN100C is slightly smaller than that of Sn-37Pb at the shear speed of 1000 mm/sec, while the Sn-3.0Ag-0.5Cu fracture area is much less than Sn-37Pb due to its low ductility and brittleness. Comparing the fracture areas, Sn-37Pb>SN100C>Sn-3.0Ag-0.5Cu.
In general, a solder alloy with a larger fracture area can absorb greater energy and shock due to its ductility and ability to deform. Additionally, Sn-3.0Ag-0.5Cu is brittle and resistant to deformation, where SN100C is ductile like Sn-37Pb. Furthermore, SN100C(Sn-0.7Cu-0.05Ni+Ge) has no shrinkage defects, reduced copper erosion, and its' high ductility inhibits growth of the IMC layer.
For more information about Nihon Superior's SN100C High Ductility Lead-free Solder, visit http://www.nihonsuperior.co.jp.
About Nihon Superior Co. Ltd.
Nihon Superior was founded in 1966 when it began marketing unique flux products imported from the US. The company made its mark on society by gathering the most advanced soldering and brazing technologies and products from around the world, and supplying them to companies in the metal-joining industry. A turning point for the company came when it started developing its own soldering materials and with the success of its unique SN100C lead-free solder alloy Nihon Superior has become a major player in the global market. To support the growing demand for its products Nihon Superior has established manufacturing and sales centers in Japan, China and other Asian countries and formed business partnerships with companies in other markets.