While the situation varies from country to country, nearly one year after the EU RoHS Directive came into force implementation of lead-free solder is progressing steadily. For lead-free soldering to be considered successful it is not sufficient just to have dealt with the challenges of mass production. It is also necessary to establish that the soldered joints produced are at least as reliable ...

Chemical syntheses of homogenous solid solution alloy nanoparticles of noble metals require high temperature above 100 °C. Beside this, aqueous co-reduction methods lead to phase separation. In contrast, pulsed laser ablation in liquid (PLAL) allows synthesis of alloy nanoparticles with totally homogeneous ultrastructure in aqueous media at room temperature without reducing agents or organic li...

3.2 Enthalpies, entropies (solid and liquid state) – free energy and entropy of mixing The heats of formation of six solid Pb-Bi alloys have been measured at 400 K in a liquid lead solution calorimeter by P. Roy, et al. They found that these alloys obey Kopp’s law of additivity and the heats of formation are therefore temperature independent. The lead and bismuth used in these experiments were ...

Traditional Sn-Pb solder alloys are being replaced, because of environmental and health concerns about lead toxicity. Among some alternative alloy systems, the Sn-Zn and Sn-Cu base alloy systems have been studied and reveal promising properties. The reliability of a solder joint is affected by the solder/substrate interaction and the nature of the layers formed at the interface. The solder/subs...

Currently, the portable electronic products trend to high speed, light weight, miniaturization and multifunctionality. In that field, solder joint reliability in term of both drop impact and thermal cycling loading conditions is a great concern for portable electronic products. The transition to lead-free solder happened to coincide with a dramatic increase in portable electronic products. Sn–A...