Different variations of lead-free solder require individualized production processes according to an article on the Sweden-based website, Evertiq. According to Dr. Dongkai Shangguan, VP for advanced technology at EMS-provider Flextronics, different variations of Sn-Ag-Cu (SAC) with silver content from 3.0 percent to 4.0 percent are all acceptable compositions for lead-free soldering, including reflow and wave soldering.
However, Shangguan notes that when the silver content is much lower, such as SAC105, the thermomechanical reliability performance is adversely affected due to the reduced amount of Ag-Sn intermetallic compound in the solder microstructure.
The article goes into detail on subjects of lead-free solder compatibility, board layout design, PCM pad cratering, process challenges, lead-free solder reliability and process control.
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This discussion will examine what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.