Issue link: https://iconnect007.uberflip.com/i/1207026
70 SMT007 MAGAZINE I FEBRUARY 2020 reliability—that is, until the advent of lead-free, a well-meaning but ill-conceived and poorly executed conversion, forced on the industry by the European Union in 2006. While the purveyors of prospective lead-free solder solutions asserted that they had every- thing under control, nothing could have been further from reality. After the rollout of the first high-temperature SAC alloys, the industry quickly found out how vulnerable their pro- duction lines and products really were. More than $100 billion has since been spent trying to find the equivalent of the tried, tested, and trusted tin-lead alloys. One of the most frustrat- ing things about the forced conversion was that the stated reasons for risk to all human health w e r e m a s - sively over- s t a t e d . T h e r e w e r e admittedly p e o p l e i n China and South Asia who suffered injury from lead in electronic sol- der, but their injuries were the result of the craven behavior of economic opportunists dumping electronic waste in those places without providing the tools and training to the local people to do so safely. In short, lead used in solder for electronics products represented at the time less than 0.5% of all lead consumed on an annual basis. It was like using a cannon to kill a fly. Article by Joe Fjelstad VERDANT ELECTRONICS Solder is a marvelous material for joining metal parts together at relatively low tem- peratures. The first use of solder to join met- als (mostly for adornments and some simple tools) came on the heels of the discovery of tin in Britain some 4,000 years ago, according to technology historians. The base metal and later simple alloy's utility found for it an ever- expanding roll in civilization and industry for items as disparate as joining water piping, sealing automo- tive radiators, a n d m a k i n g s t a i n e d - g l a s s windows. How- ever, its crown- ing role for most of the last century has been for joining electrical and elec- tronic elements of electronic prod- ucts, from simple spliced wires to the most advanced chips and chip packages of the present day. For most of its historical use in electron- ics, the solder alloy of choice was tin-lead, either an Sn60/Pb40 alloy or the Sn63/ Pb37 eutectic version of the tin-lead alloy. These two alloys were the workhorses of the industry. They were both well under- stood in terms of their processing and Solder in PCBA: Can't Live Without It... or Can We?