WS353 water soluble solder paste has been developed in response to electronics manufacturers demand for an all-purpose, reliably consistent water-soluble solder paste. WS353 offers extended stencil life and tack time, robust environmental tolerance and printing characteristics, excellent activity, a broad cleaning process window, and compatibility with both tin-lead and lead-free solder alloys. WS353 can be used in fine pitch printing applications and has proven effective in the assembly of 0201 components. WS353 provides consistent printing characteristics and slump resistance during high-speed printing. The excellent activity of WS353 makes it a suitable choice when soldering to standard or difficult-to-wet parts, including lead-free alloys and finishes. In addition, WS353 has proven to substantially reduce voiding under micro-BGAs. The residues of WS353 may be cleaned easily in straight water, with the result being exceptional electrical reliability. In addition, WS353 is designed to not foam during washing, even in high-pressure wash systems.
Features
* Broad Printing Process Window
* Excellent Wetting
* Easily Cleaned Residues
* Lengthy Stencil Life and Track Time
* Reduces Voiding Under BGAs
* Low Foaming During Washing
Paste Application
* Apply sufficient paste to the stencil to allow a smooth, even roll during the print cycle (a bead diameter of 12-16mm is normally sufficient to begin).
* Apply small amounts of fresh solder paste to stencil at controlled interval to maintain paste chemistry and workable property.
* WS353 provides the necessary track time and force for today’s high speed placement equipment. which will enhance product performance and reliability.
* Cleaning of your stencil will vary by application; however, it can be accomplished using AIM 200AX-10 stencil Cleaner.
Printer Set-Up
* Snap-off Distance = On Contact 0.00 mm (0.00″)
* PCB Separation Distance = 0.75-2.0 mm (0.030 – 0.080″)
* PCB Separation Speed = Slow – Medium
* Squeegee Pressure = 0.30 – 0.75 kg/cm (0.6 – 1.7 lbs/In.) of blade
* Squeegee Stroke Speed = 25 – 50 mm/sec (1 – 2 In./sec)
NOTE: recommended initial printer settings above are dependent on the PCB and pad design.
WS353 Compatible Products
* Electropure Solder Bar
* WS Tacky Flux
* WS482 Cored Wire
*WS715; WS735 Spray Flux
* Epoxy 4089 – Chip Bonding Epoxy
* 200AX – Stencil Cleaner
Physical Properties
Appearance – Gray, smooth, creamy
Alloy – SN63 and SN62
Melting Point – 183°C
Particle Size – T3, T4, T5
General Melt Loading – 89.5% (T3)
Viscosity – Print/Dispense
Packaging – Available in all industry standard packaging
Cleaning
WS353 can be cleaned easily with normal tap water. Deionized water is recommended for the final rinse. A temperature of less than 120°F is sufficient for removing residues. An in-line or other pressurized spray cleaning system is suggested, but is not required.
Handling and Storage
* WS353 has a refrigerated shelf life of 6 months at 4°C – 12°C (40°F – 55°F)
* Recommended operating environment 35-55% Rh and 20°C to 23°C (68°F to 74°F). Product is capable of performing from 5-70% Rh and 20°C to 30°C (68°F to 85°F) with suitable printer settings for the conditions.
* Allow the solder paste to warm up completely naturally to ambient temperature (8hrs) prior to breaking the seal for use. Do not force warm.
* Mix the product lightly and thoroughly (1-2 mins max) to ensure even distribution of any separated material.
* Do not store new and used paste in the same container, and reseal any opened containers while not in use.
* Replace the internal plug and cap in the 500g jars to ensure the best possible seal.
