DESCRIPTION
RMA 202-25 is a medium solids, mildly activated liquid flux with a solvent rosin activation formulated to provide a post-process flux residue that is both insulating and non-hydroscopic and does not require cleaning. As a mildly activated rosin based flux, RMA 202-25 offers a wide process window, good cleaning properties, and excellent thermal transfer.
FEATURES
- ROSIN ACTIVATED
- IMPROVED SOLDERING PERFORMANCE
- NON CORROSIVE RESIDUES
- RESIDUES REMOVABLE WITH A SAPONIFIER
- NON-HYDROSCOPIC RESIDUES
- CAN BE FOAMED, SPRAYED, DIPPED OR BRUSHED
** Passes IPC SIR. Testing results available upon request. Complies with IPC-J-STD-004 and MIL-STD-F14256.
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Solids Content 25% |
Flux Density .84 ± .02 |
Acid Number 40.5 ± .05 |
HANDLING
- RMA 202-25 has an unopened shelf life of 1 year when stored at room temperature.
- Do not store near fire or flame. Keep away from sunlight as it may degrade product.
- RMA 202-25 is shipped ready-to-use, no mixing is necessary.
- Do not mix used and unused chemical in the same container. Reseal any opened containers.
FLUX APPLICATION
• When being used for rework, application should be limited to the area being worked. AIM Flux Dispensers or a cotton swab are recommended for localized flux application.
• For most tinning operations, the component lead should be immersed into the flux to a depth of approximately 50% of the desired solder flow in order to prevent excessive flux application.
• For spray fluxing applications, RMA 202-25 is ready to use directly from its container, no thinning is required.
• When spray fluxing, it is imperative that proper flux coverage and uniformity be achieved and maintained. A dry flux coating of 500 to 1500 micrograms per square inch is recommended as a starting point.
• When foam fluxing, air stones should be supplied with compressed air, free of oil and moisture. Adjust foam head to achieve a uniform distribution of small bubbles for optimum flux coverage.
• During foaming applications it is periodically necessary to add flux thinner to replace that which is lost through evaporation. AIM Common Flux Thinner is recommended.
PROCESS CONTROL
Specific gravity should be monitored and controlled either with automated equipment or manually with a hydrometer. Specific gravity should be maintained at .84 ± .02 for optimum performance. Dump and refill flux pot with fresh flux at least once per week when used daily. For spray flux applications, ensure that proper coverage of pwb is maintained.
FLUX TECH-TIPS
PROBLEM and POTENTIAL CAUSE
- BRIDGING: INSUFFICIENT FLUX, EXCESSIVE PRE-HEAT, EXCESS CONVEYOR SPEED, SOLDER CONTAMINATION
- SOLDER BALLS: LOW PREHEAT TEMPERATURE, EXCESS FLUX
- WHITE RESIDUE: EXCESS FLUX, FLUX CONTAMINATION, SOLDER CONTAMINATION
- DISCOLORED JOINT: SOLDER OXIDATION, BOARD/COMPONENT CONTAMINATION, EXCESSIVE HEAT
