Properties and Microstructures of Sn-Bi-X Lead-Free Solders

Figure 8

BEI micrographs of large reaction couples reacted at 160°C for 10 min: (a) Sn-57 wt.% Bi/Cu, (b) Sn-57 wt.% Bi-0.05 wt.% Co/Cu, and (c) Sn-57 wt.% Bi-0.5 wt.% Co/Cu [49].

(a)

(b)

(c)