Sn42Bi58 T4 solder powder

The Sn42Bi58 T4 solder powder is a lead-free tin-bismuth alloy with a low melting point of approx. 138 °C. With 58 % Bismuth This alloy is particularly suitable for Temperature-sensitive electronicswhere conventional solders would cause too high thermal loads. Due to the T4 grit (20-38 µm) the powder enables even more precise paste deposition than the T3 variant and is ideal for fine-pitch and LED applications.

Properties and advantages

• Low melting point (~138 °C): Ideal for sensitive components such as LEDs, sensors and thin-film electronics.
• Fine T4 grit: Improved stencil printing results and higher resolution for dense PCB layouts.
• Lead-free & RoHS compliant: Sustainable solution for modern electronics production.
• Very good wetting: Uniform, homogeneous solder joints with high process reliability.
• Cost efficiency: Attractive alternative to silver solders with a defined temperature profile.

Areas of application

Fine-Pitch & LEDs

Due to the fine T4 grit Sn42Bi58 is suitable for high-density assemblies and LED solutionswhere precise paste deposition is crucial. Minimised bridging and clean solder joints are the result.

SMT & reflow processes

Especially in Semiconductor Technology & Electronics the powder is convincing in stencil printing and reflow soldering, where precise wetting and defined process windows are required.

Hard & soft soldering

In the area Hard & soft soldering the alloy offers reproducible results in applications with clearly defined melting points.

Automotive industry & electrical engineering

In the Automotive industry and Electrical engineering Sn42Bi58 T4 is used when assemblies with a high packing density must be thermally protected and reliable solder joints are still required.

Technical properties

• Composition: Sn 42 %, Bi 58 %
• Melting point: approx. 138 °C
• Grain size: T4 (typically 20-38 µm)
• Particle morphology: spherical for precise paste rheology
• Quality: High purity, low oxidation

Sustainability & regulation

Sn42Bi58 T4 is lead-free and fulfils the RoHS requirements. Thanks to its low melting point, it reduces the thermal load on sensitive components and at the same time saves energy in the soldering process - an advantage for the environment and efficiency.

Conclusion

Sn42Bi58 T4 solder powder is the ideal choice for fine-pitch, LED and SMT applications that require a Low-melting, lead-free solder require. With its finer grain size compared to the T3 version, it offers even more precise paste application and greater process reliability. Further possible applications can be found in the following areas Semiconductor Technology & Electronics and Hard & soft soldering.