Patent ID: 8530058

Claim:
A lead free solder alloy consisting essentially of about 3.9 weight percent Ag, 0.7 weight percent Cu, Ce of about 0.1 to 2.0 weight percent, and the balance Sn, wherein Sn, Ag, and Cu form a ternary eutectic composition in a matrix, and characterized by: homogeneously distributed fine grain CeSn 3 intermetallic particles dendritic in morphology, wherein the CeSn 3 intermetallic particles are substantially uniformly distributed and below an outer surface, Sn dendrites, and a eutectic phase consisting of Sn, Ag 3 Sn and Cu 6 Sn 5 particles, and wherein the alloy exhibits an oxidation rate of 4.5×10 −4 , K p (mg/cm 2 h 1/2 ), or less at 60′C and an at least 70% increased ductility relative to a Sn—Ag—Cu alloy consisting of about 3.9 by weight percent of Ag, 0.7 by weight of Cu, and a balance of Sn.