When electronic assemblies generate heat, component longevity and reliability depend on how effectively that heat is managed. Thermally conductive encapsulants have become one of the most trusted solutions for engineers who need to simultaneously protect electronics and dissipate heat — all within a single material.
At DGE Europe, we supply the DOWSIL™ TC Series from Dow, a family of high-performance thermally conductive encapsulants built on decades of proven silicone technology. These materials have demonstrated reliable performance under the harshest operating conditions, resisting shock, oxidation and moisture while maintaining their mechanical and chemical properties across a temperature range of -40°C to 200°C.
What Are Thermally Conductive Encapsulants?
Thermally conductive encapsulants are flowable silicone-based materials designed to fill cavities around electronic components, creating a protective and thermally efficient interface between heat-generating parts and the surrounding structure.
Unlike pre-cured thermal pads, these liquid encapsulants adapt to complex geometries and integrate seamlessly into automated high-volume production processes. For a broader overview of conductive compound solutions for thermal management, see our dedicated guide. Once cured, they provide lightweight thermal coupling between cells and modules — a critical advantage in weight-sensitive applications like aviation and automotive electronics.
Their dual function makes them a practical choice:
- Thermal management: they conduct heat away from sensitive components
- Environmental protection: they seal against moisture, shock and oxidation
DOWSIL™ TC Series: Five Products for Every Thermal Challenge
Dow’s DOWSIL™ TC Series comprises five distinct thermally conductive encapsulants, each engineered for a specific balance of thermal conductivity, viscosity, hardness and pot life. All five products are two-component systems and share a 9-month shelf life.
DOWSIL™ TC-6011 Thermally Conductive Encapsulant
The TC-6011 is the entry point of the series, offering the lowest viscosity (3,000 mPa·s) and the most flowable handling characteristics. Its long pot life of 135 minutes at 25°C makes it ideal for complex potting processes where extended working time is required.
| Property | Value |
| Mixed viscosity | 3,000 mPa·s |
| Pot life @25°C | 135 min |
| Density | 1.65 g/cm³ |
| Hardness | Shore A 28 |
| Thermal conductivity | 1.0 W/m·K |
| Dielectric strength | 21 kV/mm |
| Tensile strength | 0.62 MPa |
| Elongation | 70% |
| Flame classification | UL94 V-0 |
| Heat curing | 40 min @100°C |
Best for: Applications where maximum flowability and long pot life are priorities, combined with basic thermal management needs.
DOWSIL™ TC-6015 Thermally Conductive Encapsulant
The TC-6015 steps up thermal performance to 1.6 W/m·K while maintaining a relatively low viscosity. Its shorter cure cycle (30 min @70°C) suits production environments where throughput is key.
| Property | Value |
| Mixed viscosity | 4,000 mPa·s |
| Pot life @25°C | 90 min |
| Density | 2.25 g/cm³ |
| Hardness | Shore A 40 |
| Thermal conductivity | 1.6 W/m·K |
| Dielectric strength | 15.3 kV/mm |
| Tensile strength | 0.70 MPa |
| Elongation | 30% |
| Flame classification | UL90 V-0 |
| Heat curing | 30 min @70°C |
DOWSIL™ TC-6020 Thermally Conductive Encapsulant
With 2.7 W/m·K thermal conductivity and the highest Shore A hardness in the series (63A), the TC-6020 is designed for applications requiring robust mechanical protection alongside significant heat dissipation. It cures at a low temperature of 60°C, reducing energy consumption during production.
| Property | Value |
| Mixed viscosity | 10,640 mPa·s |
| Pot life @25°C | 77 min |
| Density | 2.93 g/cm³ |
| Hardness | Shore A 63 |
| Thermal conductivity | 2.7 W/m·K |
| Dielectric strength | 24.1 kV/mm |
| Tensile strength | 0.95 MPa |
| Elongation | 20.6% |
| Flame classification | N/A |
| Heat curing | 23 min @60°C |
Notable: Highest dielectric strength in the series at 24.1 kV/mm, making it a strong candidate for high-voltage encapsulation applications.
DOWSIL™ TC-6032 Thermally Conductive Encapsulant
The TC-6032 offers 3.2 W/m·K thermal conductivity with the longest pot life in the series — 240 minutes at 25°C. This combination is exceptional for large-format assemblies or batch processes where material must remain workable for extended periods.
| Property | Value |
| Mixed viscosity | 6,500 mPa·s |
| Pot life @25°C | 240 min |
| Density | 2.73 g/cm³ |
| Hardness | Shore A 34 |
| Thermal conductivity | 3.2 W/m·K |
| Dielectric strength | 18 kV/mm |
| Tensile strength | 0.50 MPa |
| Elongation | 45% |
| Flame classification | UL94 V-0 |
| Heat curing | 60 min @80°C |
Distinctive feature: Part B and mixed color is blue, simplifying visual quality control on the production line.
DOWSIL™ TC-6040 Thermally Conductive Encapsulant
The TC-6040 is the flagship of the series, delivering 4.0 W/m·K thermal conductivity — the highest value across the entire TC family. Despite its superior thermal performance, it maintains a surprisingly soft Shore A 32 hardness, which protects delicate components from thermomechanical stress.
| Property | Value |
| Mixed viscosity | 33,000 mPa·s |
| Pot life @25°C | 120 min |
| Density | 3.05 g/cm³ |
| Hardness | Shore A 32 |
| Thermal conductivity | 4.0 W/m·K |
| Dielectric strength | 15 kV/mm |
| Lap shear Al/Al | 0.1 MPa |
| Flame classification | UL94 V-0 |
| Heat curing | 60 min @100°C |
Best for: High-power electronics where maximum thermal dissipation is non-negotiable.
Full Comparison: DOWSIL™ TC Series at a Glance
| Property | TC-6011 | TC-6015 | TC-6020 | TC-6032 | TC-6040 |
| Thermal conductivity (W/m·K) | 1.0 | 1.6 | 2.7 | 3.2 | 4.0 |
| Mixed viscosity (mPa·s) | 3,000 | 4,000 | 10,640 | 6,500 | 33,000 |
| Pot life @25°C (min) | 135 | 90 | 77 | 240 | 120 |
| Hardness (Shore A) | 28 | 40 | 63 | 34 | 32 |
| Density (g/cm³) | 1.65 | 2.25 | 2.93 | 2.73 | 3.05 |
| Dielectric strength (kV/mm) | 21 | 15.3 | 24.1 | 18 | 15 |
| Shelf life (months) | 9 | 9 | 9 | 9 | 9 |
Key Benefits of DOWSIL™ Thermally Conductive Encapsulants
Low Viscosity for Process Efficiency
The flowable nature of these silicone encapsulants facilitates automated dispensing in high-volume production lines, reducing cycle times and minimizing waste.
Combined Protection and Heat Dissipation
A single material provides both environmental sealing and thermal management — eliminating the need for separate thermal interface materials and conformal coatings in many designs.
Low Modulus
Soft, flexible cured properties reduce mechanical stress on components caused by thermal cycling, vibration or shock — critical in automotive and aviation environments.
Primerless Options Available
Select products in the TC series adhere without a primer, simplifying surface preparation and reducing assembly steps.
Proven Operating Range
Consistent performance from -40°C to 200°C means these encapsulants meet the demands of the most challenging thermal environments, from under-bonnet automotive electronics to industrial inverters.
Applications for Thermally Conductive Encapsulants
The DOWSIL™ TC Series is qualified and used across multiple industries:
- Automotive — ECU, onboard charger modules, inverters
- Solar — junction boxes, power conversion modules
- Power electronics — capacitor banks, rectifiers, transformers
- Industrial — control panels, motor drives
- Aviation — avionics, embedded electronics
- Inverters and OCB — thermal protection for power switching components
- Lighting modules — LED driver encapsulation
- Display systems — driver board protection and heat management
Important Considerations When Selecting a Thermally Conductive Encapsulant
When choosing between the five TC Series products, engineers should evaluate:
- Thermal conductivity requirement — higher filler loading (TC-6032, TC-6040) delivers greater heat dissipation but increases density and viscosity.
- Mechanical protection needs — higher hardness (TC-6020 at Shore A 63) offers more rigid protection; lower hardness grades are better for stress-sensitive assemblies.
- Process window — TC-6032 with its 240-minute pot life is best for large assemblies; TC-6020 cures fastest at only 23 minutes at 60°C.
- Filler settlement — as with all highly filled silicone systems, proper mixing procedures and dispensing equipment should be used to ensure homogeneity.
Frequently Asked Questions
What is the difference between a thermally conductive encapsulant and a thermal pad?
Thermal pads are pre-cured solid sheets requiring mechanical fixation. Thermally conductive encapsulants are liquid before curing, allowing them to fill irregular geometries completely, eliminate air voids, and be applied via automated dispensing — making them preferable for high-volume production.
What thermal conductivity range does the DOWSIL™ TC Series cover?
The TC Series spans from 1.0 W/m·K (TC-6011) to 4.0 W/m·K (TC-6040), covering most industrial and automotive thermal management requirements.
Are DOWSIL™ TC encapsulants flame-retardant?
Most products in the series carry a UL94 V-0 flame classification, the highest rating for self-extinguishing performance.
What is the shelf life of DOWSIL™ TC products?
All five products in the TC Series have a shelf life of 9 months.
Can these encapsulants be used in automotive applications?
Yes. The TC Series is rated for operating temperatures between -40°C and 200°C, covering the full automotive temperature specification.
Why Source DOWSIL™ TC Series Through DGE Europe?
DGE Europe is an authorised distributor of Dow silicone materials, offering technical support, reliable stock availability, and expert guidance in product selection for thermal management applications.
Whether you’re designing a high-power EV inverter, an industrial motor drive, or a high-luminosity LED module, our team can help you select the right thermally conductive encapsulant for your performance, process and cost requirements.
All technical data sourced from Dow’s official electronics documentation.
