JERSEY CITY, N.J. — Cookson Electronics Assembly Materials (CEAM) introduced ALPHA WS-819 water-soluble lead-free solder paste for PCB assembly of high-reliability end products. The paste targets cleanability, voiding resistance, and printing compatibility.

CEMA developed the Type 3 paste based on customers' reported key process indicators (KPIs) of long stencil life, printability over a range of humidity conditions, aqueous cleaning, and low voiding. WS-819 can be used in humidity of 50% ±15% and suits organic solderability preservative (OSP), immersion silver, immersion tin, and electroplated nickel immersion gold (ENIG) surface finishes. It is said to reduce printing cycle times and offer eight-hour stencil life. The paste is available as SAC 305 and 405 alloys and print volume repeatability down to 0.3-mm features. Water cleaning eliminates saponifiers, waste-water treatment, and special waste-disposal systems.