WACKER SilGel® 612 A/B
WACKER SilGel® 612 A/B is a pourable, addition-curing, RTV-2 silicone rubber that vulcanizes at room temperature to a very soft silicone gel.
Main application:
- Electronic Control Unit (ECU)
- Electronics
- Heating, Ventilation, Air Conditioning (HVAC)
- Potting & Encapsulation
- Power Control Unit (PCU)
Application details
- encapsulation of electronic components for the automotive and power electronics industries
- encapsulation of solar cells
- production of damping elements
- sealing of clean room filters
Characteristics
- Mixing ratio: 1:1 mixing ratio
- Low viscosity: 1000 mPa.s, good fluidity
- Two-component platinum hardening.
- Density: 0.97 g/cm³
- Volume resistivity: 10 15 Ohm.cm
- Permitivity: 2.7
- Color: Clear
- Flame retardancy: 94 HB
- Penetration: 300 1/10mm
- Refractive index nD²⁵ : 1.404 @ 25C
Processing
Please note: Only components A and B with the same lot number may be processed together!
Surface preparation:
All surfaces must be clean and free of contaminants that will inhibit the cure of WACKER SilGel® 612 A/B. Examples of inhibiting contaminants are sulfur containing materials, plasticizers, urethanes, amine containing materials and organometallic compounds – especially organotin compounds. If a substrate’s ability to inhibit cure is unknown, a small-scale test should be run to determine compatibility.
Mixing
Component B of WACKER SilGel® 612 A/B contains the platinum catalyst, component A the crosslinker. Even traces of the platinum catalyst may cause gelling of the component containing the crosslinker. The two components should be thoroughly mixed at a 1 : 1 ratio by weight or volume. To eliminate any air introduced during dispensing or trapped under components or devices a vacuum encapsulation is recommended.
Curing :
Curing time of addition curing silicone rubber is highly dependent on temperature, size and heat sink properties of the component being potted.
Hardness:
If the gel is too soft and tacky, reducing the amount of component B will result in a harder, less tacky vulcanizate. The hardest formulation is achieved with a mixing ratio for A : B of approximately 1.5 : 1.
For logistical reasons we can only accept orders in a mixing ratio of A : B = 1 : 1.
Tack-free surfaces can be achieved by coating with ELASTOSIL® RT 601.
Additives
WACKER SilGel® 612 A/B can be pigmented by adding 1 - 4 % of an ELASTOSIL® FL pigment paste.
The reactivity can be adjusted within wide limits by adding ELASTOSIL® Catalyst EP or Inhibitor PT 88 to suit the processing requirements of the particular application. ELASTOSIL® Catalyst EP increases the reactivity, i. e., pot life and curing time are reduced. Inhibitor PT 88 is a pot life extender and prolongs pot life and curing time.
Further information is given in our leaflet “ELASTOSIL®Catalyst EP / Inhibitor PT88”.
We recommend running preliminary tests to optimize conditions for the particular application.
Comprehensive processing instructions are given in our leaflet "Wacker RTV-2 Silicone Rubber-Processing".
Packaging and storage
The 'Best Before' date of each batch is stated on the product label. Storage after the date stated on the label does not necessarily mean that the product is no longer usable. However, in this case, the properties required for the intended use must be checked for quality assurance reasons.
Safety instructions
According to the latest insights, the addition-curing silicone rubber WACKER SilGel® 612 A/B does not contain any toxic or corrosive substances that require special precautions when handling.