LONDON -- The SMART Group, a UK-based SMT professional society, has released its first standard, “Control of Solder Paste used in Electronic Assembly Process.”

SG PCT01 intends to help electronics assemblers to determine the suitability of the solder paste prior to production. The tests show the actual useful life of the paste, in order to reduce waste and environmental impact. The test methods employed are adaptations of the methods employed by paste manufacturers found in IPC-TM-650, J-STD-004/5 and IEC 61189-5. They assess solder paste for slump, spread, wetting, tack and balling.

Included are data providing the open time of a selected paste.

The standard is reportedly the first to set forth a user-friendly procedure that may be conducted in less than 1 hour. It relies on simple ceramic or copper-clad FR-4 coupons, with solder paste applied using special stencils applicable to the test in question.

In a statement, SMART Group vice chairman Graham Naisbitt, who initiated the standard, said, “This document is an important new development to our membership and beyond. Process control tests are in high demand but have not been easy to implement because invariably [they] result in arguments between user and supplier. What we have set out to achieve is a careful balance of the needs of each and of enhancing the user/supplier relationship.”