Low-residue soldering of military electronics

In support of the Montreal Protocol and a directive from former President George Bush to phase out production of ozone-depleting chemicals (ODCs), Texas Instruments Incorporated (TI) mandated the elimination of ODCs from TI operations by the end of 1994. ODCs were used extensively in the TI Defense Systems and Electronics business for cleaning circuit card assemblies (CCAs) after soldering. In 1991, TI began evaluating low-residue flux (LRF)/controlled atmosphere soldering (CAS) as an alternative to cleaning rosin flux residues from CCAs with ODCs. This paper details TI's evaluation and successful implementation of the LRF/CAS process in the production of military electronics. This process is approved for use on 60 military programs at TI ESD in McKinney, Texas, USA.