Premium Very Soft Encapsulant Silicone Gel for Professional Electronics and Power Electronics Applications

WACKER SilGel® 612 A/B is a pourable, addition-curing (platinum-cure) RTV-2 silicone gel that cures at room temperature to a crystal clear, very soft gel. The two-component gel is mixed in a 1:1 weight ratio (A:B), has a low viscosity of 1000 mPa·s for excellent flowability, and achieves a density of 0.97 g/cm³ after curing. Its softness is expressed in penetration (300 1/10 mm) instead of Shore hardness, which is characteristic of a true silicone gel. With a pot life of approximately 150 minutes at 23 °C and a cure time of 8 hours at 23 °C or 15 minutes at 100 °C, the gel offers ample processing time combined with rapid heat curing. The combination of extremely low modulus, high dielectric strength, and excellent chemical purity makes this gel ideal for protecting sensitive electronics against vibration, moisture, and thermomechanical stress.

Key Benefits

• Penetration 300 1/10 mm – very soft gel with extremely low modulus that absorbs thermomechanical stress without transferring it to sensitive components
• Dielectric strength > 23 kV/mm – reliable electrical insulation that prevents leakage currents and breakdown in power modules
• Volume resistivity 10¹⁵ Ohm·cm – excellent insulation resistance that remains stable over a wide temperature range
• Density 0.97 g/cm³ – lightweight, low-stress encapsulation with good flowability for complete filling of complex geometries
• Pot life 150 minutes at 23 °C – ample processing time with the option of rapid heat curing in 15 minutes at 100 °C
• Flame retardant UL 94 HB – meets the UL 94 HB flammability rating for use in electronic enclosures

Typical Applications

• Encapsulation of electronic components for the automotive and power electronics industries (ECU and PCU)
• Selective potting and dam-and-fill protection of PCBs and power modules
• Encapsulation of solar cells and photovoltaic assemblies
• Production of vibration-damping elements
• Sealing of cleanroom filters
• Protection of sensors and control units in heating, ventilation, and air conditioning (HVAC)

Processing Instructions

1. First, stir component A and component B thoroughly and separately.
2. Mix component A and B in a 1:1 weight or volume ratio. Please note: use only components A and B from the same lot number, as different lot numbers can interfere with curing.
3. Mix slowly and thoroughly until a homogeneous mixture is achieved, to minimize air entrapment.
4. Degas the mixture under vacuum to remove entrapped air; this is recommended when encapsulating components.
5. Pour the mixture within the pot life of approximately 150 minutes at 23 °C.
6. Allow to cure for 8 hours at 23 °C or accelerated for 15 minutes at 100 °C. Curing time is highly dependent on temperature, layer thickness, and the heat dissipation of the encapsulated part.

About the Manufacturer

Wacker Chemie AG is a global market leader in the development and production of silicones for industrial and technical applications.

Professional Support

Do you need advice on the right encapsulation or protection gel for your electronics application, on adjusting pot life with ELASTOSIL® Catalyst EP or Inhibitor PT 88, or on processing and curing? Please feel free to contact us. The Silicones and More team will be happy to assist you with material selection, dosing, and processing.