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DOWSIL™ TC-6040 Thermal Conductive Encapsulant
- Heat accelerated cure
- Room temperature cure
- 4.0 W/m·K flowable silicone encapsulant
Product Description
DOWSIL™ TC-6040 Thermal Conductive Encapsulant is a two-part, high-flow silicone encapsulant designed to provide advanced thermal management, electrical insulation, and environmental protection for high-power electronic assemblies. With 4.0 W/m·K thermal conductivity, self-leveling flow, controlled volatility, and UL 94 V-0 certification, TC-6040 helps dissipate heat from sensitive components while protecting them from moisture, contaminants, vibration, and electrical stress. It cures at room temperature or through heat acceleration, making it suitable for both manual and automated dispensing processes. Designed for demanding applications such as EV controllers, on-board chargers, inverters, converters, power supplies, control units, lighting assemblies, and energy conversion systems, TC-6040 supports long-term reliability at elevated operating temperatures.
Key Features
4.0 W/m·K thermal conductivity for efficient heat dissipation.
Two-part 1:1 silicone encapsulant for reliable processing.
High-flow, self-leveling formulation for complete component coverage.
Room-temperature cure in 24 hours at 25°C.
Heat-accelerated cure in 60 minutes at 100°C.
Controlled volatility for improved long-term electronics reliability.
Minimal filler settling and easy remixing for smoother processing.
Excellent dielectric strength of 15 kV/mm.
High volume resistivity of ≥1.0 × 10¹³ Ω·cm.
UL 94 V-0 certification for flame-rated electronic assemblies.
Suitable for long-term use at +150°C and short-term exposure to +200°C or higher.
Suitable for EV controllers, on-board chargers, inverters, converters, power supplies, control units, electronic modules, lighting assemblies, and energy conversion systems.
Technical Specifications
| General Properties | |||||||
| Color Color The color | Part A: White | Part B: Pink | ||||||
| Component System Component System Describes the number of components that must be supplied, mixed, or activated before application or cure. | Two Part | ||||||
| Mix Ratio Mix Ratio The amount of a constituent divided by the total amount of all other constituents in a mixture | 1:1 | ||||||
| Specific Gravity Specific Gravity Specific gravity (SG) is the ratio of the density of a substance to the density of a reference substance; equivalently, it is the ratio of the mass of a substance to the mass of a reference substance for the same given volume. For liquids, the reference substance is almost always water (1), while for gases, it is air (1.18) at room temperature. Specific gravity is unitless. | 3.05 | ||||||
| Physical Properties | |||||||
| Viscosity (Part A) | 26000 mPa.s | ||||||
| Viscosity (Part B) | 22000 mPa.s | ||||||
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| Curing Conditions | |||||||
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| Mechanical Properties | |||||||
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| Elongation Elongation Elongation is the process of lengthening something. It is a percentage that measures the initial, unstressed, length compared to the length of the material right before it breaks. It is commonly referred to as Ultimate Elongation or Tensile Elongation at break. | 10 % | ||||||
| Electrical Properties | |||||||
| Dielectric Strength Dielectric Strength Dielectric strength is measured in kV per mm and is calculated by the Breakdown voltage divided by the thickness of the tested material. Those two properties go hand in hand and while Breakdown voltage is always thickness dependent, dielectric strength is a general material property. As an example, the dielectric strength of Polyimide is 236 kV/mm. If we place 1mm of Polyimide between two electrodes, it will act as an insulator until the voltage between the electrodes reaches 236 kV. At this point it will start acting as a good conductor, causing sparks, potential punctures and current flow. | 15 kV/mm | ||||||
| Volume Resistivity Volume Resistivity Volume resistivity, also called volume resistance, bulk resistance or bulk resistivity is a thickness dependent measurement of the resistivity of a material perpendicular to the plane of the surface. | ≥ 1.0 E+13 Ohms⋅cm | ||||||
Additional Information
DOWSIL™ TC-6040: High-Flow Thermal Conductive Encapsulant for Power Electronics
DOWSIL™ TC-6040 Thermal Conductive Encapsulant is a two-part, flowable silicone encapsulant designed for thermal management, electrical protection, and long-term reliability in power electronics and electronic module assemblies. With 4.0 W/m·K thermal conductivity, high-flow self-leveling behavior, room-temperature or heat-accelerated cure, controlled volatility, and UL 94 V-0 certification, TC-6040 is suitable for EV controllers, on-board chargers, inverters, converters, power supplies, lighting assemblies, and other heat-generating electronic systems.
4.0 W/m·K thermal encapsulation with high-flow protection — TC-6040 combines high thermal conductivity, self-leveling flow, controlled volatility, and dielectric insulation for advanced power electronics assemblies.
The two-part silicone system cures at room temperature or with heat acceleration, enabling deep-section and confined encapsulation while providing thermal transfer and protective elastic coverage around sensitive components.
Designed for high-power electronic encapsulation — suitable for EV controllers, on-board chargers, inverters/converters, control units, power supplies and modules, lighting assemblies, and energy conversion systems.
TC-6040 self-levels after dispensing and provides reliable thermal and dielectric performance for electronic assemblies requiring high conductivity and long-term protection.
4.0 W/m·K Thermal Conductivity • High Flow / Self-Leveling • UL 94 V-0 • RT or Heat Cure
Features & Benefits
- 4.0 W/m·K thermal conductivity — supports efficient heat dissipation from power electronics.
- High-flow, self-leveling behavior — fills and levels after dispensing.
- Room-temperature cure — cures in 24 hours at 25 °C.
- Heat-accelerated cure — cures in 60 minutes at 100 °C.
- Controlled volatility — supports long-term electronic reliability.
- Minimal filler settling — designed for easier processing and remixing.
- Excellent dielectric insulation — 15 kV/mm dielectric strength.
- UL 94 V-0 certification — suitable for flame-rated electronics assemblies.
Typical Applications
- EV controllers.
- On-board chargers.
- Inverter and converter modules.
- Energy conversion systems.
- Power supplies and power modules.
- Electronic module assemblies.
- Control units.
- Lighting assembly and protection.
Thermal and Electrical Protection for High-Power Modules
Power electronics and EV systems require encapsulants that can move heat away from sensitive components while providing electrical insulation and environmental protection. DOWSIL™ TC-6040 addresses these needs with a high-flow silicone encapsulant that self-levels after dispensing, cures into a protective elastomer, and supports long-term operation at elevated temperatures.
Engineering Data for DOWSIL™ TC-6040
| Property | DOWSIL™ TC-6040 | Condition / Note |
|---|---|---|
| Type | Two-part encapsulant | Flowable silicone encapsulant |
| Mix Ratio | 1:1 | Part A : Part B |
| Color | Part A: White Part B: Pink As dispensed: Pink | Typical appearance |
| Specific Gravity | 3.05 | Part A, Part B, and as dispensed |
| Viscosity, Part A | 26,000 cP | 25 °C, shear rate 1 s-1 |
| Viscosity, Part B | 22,000 cP | 25 °C, shear rate 1 s-1 |
| Viscosity, As Dispensed | 25,000 cP | 25 °C |
| Working Life | 90 minutes | At 25 °C, time to viscosity double |
| Cure Time at 25 °C | 24 hours | Room-temperature cure |
| Cure Time at 100 °C | 60 minutes | Heat accelerated cure |
| Durometer | Shore A 32 | Cure at 100 °C for 60 minutes |
| Tensile Strength | 0.26 MPa | Typical value |
| Elongation | 10% | Typical value |
| Lap Shear Adhesion to AlClad | 0.10 MPa | Unprimed |
| Dielectric Strength | 15 kV/mm | Non-dried, 1.0 mm thickness |
| Volume Resistivity | ≥ 1.0E+13 ohm·cm | Non-dried |
| Thermal Conductivity | 4.0 W/m·K | Hot Disk |
| CTE | 100 ppm | -40 to 150 °C |
| Low Molecular Siloxane Content | 131 ppm | D4-D10, cured sample |
| Certification | UL 94 V-0 | Flame classification |
*Typical properties are not intended for specification writing. Cure condition and performance should be tested and optimized under actual application and curing environment.
Where DOWSIL™ TC-6040 Fits
- EV controllers
- On-board chargers
- Control units
- Inverters
- Converters
- Energy conversion
- Power supplies
- Power modules
- Lighting assembly protection
Mixing, Dispensing & Cure
Mixing
Mix Part A and Part B at a 1:1 ratio. Static mixing is recommended for both manual and automated processing.
Dispensing
Automated airless dispensing can help reduce voids and avoid de-airing. If de-airing is required, use vacuum until bubbling subsides.
Curing
Cures in 24 hours at 25 °C or can be heat accelerated to 60 minutes at 100 °C. Cure progresses evenly throughout the material.
How TC-6040 Supports High-Power Electronics Encapsulation
| Design Challenge | DOWSIL™ TC-6040 Benefit |
|---|---|
| Power electronics require both heat removal and circuit protection. | 4.0 W/m·K thermal conductivity and dielectric insulation support thermal and electrical protection. |
| Complex assemblies require material flow around components. | High-flow, self-leveling behavior helps fill module spaces after dispensing. |
| Production requires reliable processing and filler stability. | Minimal filler settling and easy remixing support smoother manufacturing integration. |
| Electronics may operate in elevated temperature environments. | Suitable for long-term use at +150 °C and shorter-term exposure to +200 °C or higher. |
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