Flux Coating: Methods for Controlling Amount, Uniformity, and Cleanliness

The flux needs to be sufficient to break the oxide film and promote wetting, while avoiding ineffective accumulation and the risk of residue.

Jinglian Zhongrui Technology Team

Key Points The amount of coating does not equate to greater stability. Product cleanliness, solution condition, spray coverage, drying, and joint structure together determine whether the flux effectively reaches the required locations.

Implementation Focus 1. Control oil, particles, and surface oxidation before coating. 2. Verify wet film coverage and uniformity after drying according to product areas. 3. Manage solution concentration, stirring, filtration, nozzle condition, and replenishment rules. 4. Optimize target usage in combination with soldering defects, residues, and equipment contamination trends.

Verification and Closed Loop Establish a combination of weighing, sampling inspection, and equipment point checks to make coating results quantifiable and traceable.

Project Recommendations During scheme review, input conditions, target values, verification methods, and responsible persons should be recorded in a single traceable document; if changes occur, simultaneously evaluate the impact on design, manufacturing, and delivery.Doing this can transform experience into stable and replicable engineering capability. Further reading: Solvay NOCOLOK Technical Center: https://www.solvay.com/en/brands/nocolok/technical-center Solvay NOCOLOK Technical Data: https://www.solvay.com/en/brands/nocolok/publications