Silicone systems for extreme usage conditions
FERMASIL® is our brand name for 2-component silicone systems for the production of silicone foam seals and soft elastic silicone elastomers, used for the potting and gluing of components.
FERMASIL® is applied using FIPFG dispensing technology (Formed In-Place Foam Gasket) (Formed In-Place Foam Gasket) directly to the part and cures there at room temperature.
FERMASIL® silicone systems consist of an A-component and a cross-linking B-component, which are processed in a given mixing ratio in the mixing chamber of the dispensing head. Most FERMASIL® systems react at room temperature of their own accord after the mixing of the components and create, according to the recipe, flexible silicone foam seals or permanently elastic silicone elastomers.
FERMASIL® systems are processed using 2-component low pressure mixing and dispensing systems. Both dynamic mixing systems and static mixers are suitable for the mixing. Sonderhoff recommends dynamic mixing systems for material-friendly processing.
|Physical and chemical Properties*|
|Appearance||white, grey or black, other colours upon request (also transparent)|
|Hardness||white, grey or black, other colours upon request (also transparent)|
|Compression load deflection (25% compression)||20 to 150 kPa|
|Density||from 0,3 g/cm³ to 2 g/cm³|
|Temperature resistance||from -60° C to +180° C (short time up to +350° C)|
|Tensile strength||up to 4,5 MPa [N/cm²]|
|Elongation at break||up to 600 %|
|Compression set (DVR)||> 97 % depending on test conditions|
|Water absorption||< 1 %|
|Flame retardancy||up to UL-94 HF-1 possible|
|Viscosity of the A component:||from 1.000 mPa·s (liquid) to 500.000 mPa·s (highly pasty)|
|UL50 conformity, UV resistant, low fogging, good chemical resistance, if requested IP 69K ingress protection class and NEMA 4-6p protection class are possible. Customized developments can be agreed any time on request.|
Broad spectrum of characteristics of FERMASIL® systems
Depending on customer requirements, FERMASIL® systems can express many different characteristics. Different part applications are protected effectively in extreme surroundings. Numerous FERMASIL® product family recipes are available for this..
The different softness grades and flexibilities of FERMASIL® silicone systems are maintained even at long-term temperatures of -60 to +180°C, in special cases to 250°C, and for short periods even to +350°C.
Very low water absorption (<1%)
Because of the closed-celled structure of silicone foams, they are tropicalised and wet room safe; infiltration protection to IP 69K and NEMA 4-6p are possible.
High chemical resistance
FERMASIL® silicone systems are resistant to many chemicals (e.g. Common cleaning materials, alcohols, dilute acids and alkalis, brake fluids, oils and lubricants, coolants) and are low-fogging.
Ease of flow, reactivity and colour can be multifariously varied.
Curing at room temperature
FERMASIL® silicone foams cure on the component at room temperature in a time range from approx. 20 minutes to around 12 hours, becoming a soft foam seal. The part can then be sent on to further processing.
Crystal clear or translucent silicone potting
Temperature stable to 180°C, very high tear resistance and flexural strength (example extension at break 600%), UV-stable
Flame protection in accordance with UL 94 HF-1
FERMASIL® silicone systems can be equipped with UL 94 HF-1 flame protection; any flame after this is extinguished within 10 seconds, with max. 30 seconds’ afterglow.
For FERMASIL® silicone foam seals, an ATEX approval for component applications in explosive environments e.g. mining, oil drilling is possible.
FERMASIL® – the technology
FERMASIL® sealing foams can be efficiently and accurately piped onto parts from the most varied of branches of industry using the FIPFG (Formed-In-Place Foam Gasket) technology and mixing and dispensing systems by Sonderhoff. Depending on the viscosity, they are either freely applied to the surface of the part as a paste or poured in fluid form into a groove.
The exact interplay of the most variable set-up parameters and additional functions of the mixing and dispensing machines, the exact calibration of the part and FERMAPOR® K31 foam seal within the complete construction and the right material choice ensure truly secure sealing of industrial components for the most varied uses against damp, dust and other environmental influences is achieved.
FERMASIL® – the reaction process
The reaction of FERMASIL® sealing foams is begun by the mixing of the A and B components. The reaction progresses evenly from this point at room temperature. The applied mass thus foams up into an even, closed-cell soft foam seal.
|FERMAPOR® K31 – The foaming process|
|Mixing time:||Time period in which the A and B components are mixed.|
|Reaction time:||Time period in which the FERMASIL® foam system begins to react (after approx. 15 - 60 seconds *)|
|Rise time:||Time period in which the FERMASIL® foam system expands to form the seal body (after approx. 60 - 180 seconds *)|
|Tack-free time:||Time after which the seal surface of FERMASIL® foam systems is tack free at room temperature and can be touched without causing damage (after approx. 2 - 30 minutes *)|
Time point after which FERMASIL® foam systems can bear loads or the sealed components can be assembled (after approx. 20 minutes - 12 hours *)
|* depends on the temperature conditions
FERMASIL® – The great application diversity
The FERMASIL® pallet offers effective component protection for the most diverse requirements for sealing, gluing and potting. In the table you will find a selection of different silicone systems for various industries, from lighting to control cabinet and automotive construction, to electronics, packaging and white goods.
2C addition curing
|0,70||Slightly foamed, liquid silicone system, particularly suitable for ultrasonic sensores – good ratio between resonance and absorption behaviour|
Drive belt covers
Highly viscous, stable, medium hardness, curing possible without heat treatment
Linear luminaires, e-boxes, packaging, electric enclosures
|0,30||Liquid, good fl ow, curing possible without heat|
treatment, lights with Atex approval
Potting of electronics, battery packs, potting of sensors, potting of PC boards
|1,00||very good dielectric properties, good fl ow rating, color and reactivity are adaptable to costumers’ wishes, by changing the mixing ratio also able to process gel-like.|
Packaging covers in contact with
|1,10||Soft elastomer seal with good mechanical properties|
|1,25||Use in contact with food is possible, fast curing, good mechanical properties|
E-boxes, electric enclosures,
|0,40||Liquid, PTB approved in electric enclosure applications|
|FERMASIL® 60C0-1||Electric enclosures||> 100.000||60|
|0,35||Thixotropic, stable, standard material with medium hardness, UL50E listed|
Electric enclosures with
|0,35||UL50E listed, thixotropic, stable, curing possible without heat treatment|
2C condensation curing
ceramic glass sealings,
|0,45||alkoxy cross linking, no corrosive fi ssion products while curing, very soft foam seal|
Gute Gründe für den Einsatz von FERMASIL® *
FERMASIL® systems can be used by a constant temperature up to +180°C (special types up to 250°C) and temporary up to +350°C.
FERMASIL® systems are closed-cell and therefore do not absorb water.
FERMASIL® systems are highly resistant to many chemicals.
FERMASIL® systems are hydrolysis stable and therefore suitable for the use in tropic or damp rooms.
FERMASIL® systems keep greatest possible flexibility even down to -60°C.
FERMASIL® systems are tack free in 2 - 30 minutes which depends on the thermal condition. An oven can reduce the reaction time considerably, but it is not a necessity in all cases.
FERMASIL® systems are processed using two component metering units and can be adapted anytime flexibly and quickly to other components to be sealed.
FERMASIL® systems develop a cross-linked structure which is extremely resistant to environmental effects such as humidity, dust and temperature.
FERMASIL® systems possess exceptional long-term behaviour and have almost 100% resetting ability, even after many years of continual use.
FERMASIL® systems are suitable for direct contact with food in some cases.