Sn96.5Ag3.5 T4 solder powder

The Sn96.5Ag3.5 T4 solder powder is a lead-free eutectic solder with a defined melting point of approx. 221 °C. The Silver content of 3.5 % increases the strength of the solder joints and supports reliable processing. The T4 grit (typ. 20-38 µm) is designed for high-resolution stencil printing processes, precise paste deposition and reproducible reflow results in the Semiconductor Technology & Electronics designed.

Properties and advantages

• Lead-free eutectic (~221 °C): Constant melting temperature for homogeneous, reproducible solder joints.
• Silver reinforcement (3.5 % Ag): Increases mechanical stability and reliability, even with temperature changes.
• T4 grain size (typically 20-38 µm): Very good printability, defined paste rheology and low tendency to form solder beads.
• Very good wetting: Clean, even solder joints with stable connection to pads and connections.
• Process reliability: Optimised for automated SMT and reflow processes as well as fine pitch layouts.

Areas of application

SMT, Fine-Pitch & BGA

The T4 grit supports precise stencil placement, controlled wetting and stable reflow results - ideal for fine-pitch structures and BGA/µBGA assemblies in the Semiconductor Technology & Electronics.

Printed circuit board production

In series production, the alloy impresses with its consistent melting properties, homogeneous solder joints and reliable electrical contact quality on dense PCB layouts.

Hard & soft soldering

For defined, lead-free processes in the Hard & soft soldering Sn96.5Ag3.5 is suitable for soldering thanks to its reliable flow and wetting properties and robust solder joint microstructure.

Automotive industry & electrical engineering

In the Automotive industry and the Electrical engineering the alloy is used when assemblies have to withstand vibrations and temperature cycles permanently.

Technical properties

• Composition: Sn 96.5 %, Ag 3.5 %
• Melting point: approx. 221 °C (eutectic)
• Grain size: T4 (typically 20-38 µm)
• Particle morphology: Predominantly spherical for even distribution and stable paste rheology
• Quality: Controlled purity to minimise oxidation and slag formation

Sustainability & regulation

As lead-free Sn96.5Ag3.5 alloy generally fulfils common RoHS requirements and is therefore ideally suited as a standard solder in electronics production. Other lead-free and lead-containing alloys are also available for applications with special profiles.

Conclusion

Sn96.5Ag3.5 T4 solder powder combines a precise T4 grain with the lead-free eutectic for a constant 221 °C - ideal for fine-pitch layouts, BGA/µBGA and automated SMT processes. Related fields of application can be found in the following areas Semiconductor Technology & Electronics and Hard & soft soldering.