Dielectric Silicone Gel Materials: Why should you use them?

OEM High-Voltage Power Supply Manufacturers

Potting of high-frequency transformers, power modules, and rectifiers.

Medical X-ray System Developers

Encapsulation of X-ray generators and tube head components requiring superior dielectric insulation.

Test & Measurement Equipment Suppliers

Insulation for voltage multipliers and pulse power systems.

Electrification & Rail Infrastructure

Protecting DC/DC converters and critical sensor components from vibration and electrical stress.

Electrical Insulation 

• Great electrical insulators, protecting sensitive circuits against shorting, electrical failure and voltage fluctuations. They also help distribute and manage heat for longevity i.e. LEDs or batteries

• Non-conductive which is crucial in preventing damage when used in high voltage systems 

Thermal management

• A wide operating temperature range, often from -50C to 200C, helping to stop internal components becoming heat damaged

Flexibility 

• They remain flexible after curing, stopping them from cracking and compressing protection, allowing them to absorb mechanical stress and high vibrations

• Ability to conform to irregular shapes and surfaces, ideal for smaller or more complex components

Weatherproofing

• They provide a strong moisture barrier, preventing damage and corrosion in outdoor environments or where materials will encounter liquids. 

• A high resistance to UV radiation

Easy Usability and Fast Curing 

• Most have a low viscosity making them easy to pour

• Room temperature curing

• Considered non-toxic

Why is fast curing at room temperature important?

• Faster and simpler manufacturing, essential for high volume production 

• Less downtime as less steps are needed, unlike materials which need heat or special curing equipment, making it a more cost-effective solution

• Allows for on demand use and on-site applications

Clear and Colourless

Not all dielectric silicone gels are clear and colourless but those that are, have some added benefits: 

• Allows encapsulated components to be inspected for any defects or imcomplete potting 

• Ensures coverage is even and consistent 

• Allows for maximum light transmission when used for LEDs, light sensors and optoelectronic devices, colour would absorb this light, reducing its efficiency

• Can be used across a range of materials without interfering with appearance and looks cleaner and more visually appealing

• Avoids yellowing or discolouration

Dielectric Strength & Volume Resistivity

Exceptional Flexibility (Stress Relief)

The gel structure absorbs mechanical stress from thermal cycling (expansion/contraction) and high vibration. This prevents cracking and maintains the critical seal, eliminating voids that initiate partial discharge (PD).

Insulation Performance (Corona Resistance)

Superior chemical stability resists degradation from moisture, chemicals, and the intense heat generated by power modules, ensuring the dielectric layer remains stable over time.

Low Viscosity & Flowability

Allows the material to fully penetrate complex geometries, densely packed windings, and tight spaces, guaranteeing a void-free fill that dramatically reduces the risk of PD initiation.

Reworkability

Gels can often be removed or repaired in situ, allowing HV design engineers to prototype, analyse failures, and service expensive components without replacement.