Wetting Balance

Testing Procedure

The specimen is suspended from a sensitive transducer and immersed into a temperature-controlled solder pot at a controlled rate. Data collected by the wetting balance includes the time to reach zero buoyancy and the maximum force achieved at the end of the cycle. A rapid transition to positive wetting force indicates a clean, active surface ready for assembly.

Conversely, a slow or incomplete rise suggests oxidation or contamination that will lead to defects in production. Standardized test coupons or actual production parts are used to verify that the incoming materials meet the specified solderability requirements.

Process Application

Results from these tests guide the selection of soldering parameters for new board designs. The wetting balance provides an objective alternative to the subjective dip-and-look method. It identifies subtle changes in finish quality that might be missed during a visual check.

This tool is essential for qualifying lead-free alloys which typically exhibit slower wetting times than traditional leaded solders.