Our company can customize thermal conductive silicone sheets with a thermal conductivity ranging from 1.0 to 15W. We also have products such as thermal conductive sealants, thermal conductive adhesives, and liquid adhesives. Regarding exports, our products have low thermal resistance and excellent flame retardancy. We can customize various sizes according to customers' requirements, and the colors can also be customized. For products of the same type, we also have thermal conductive silicone.
Our technicians have been engaged in the industry for more than 10 years and possess rich experience.
In the relentless pursuit of smaller, faster, and more powerful electronic devices, one persistent challenge remains: heat. Excessive heat is the nemesis of electronic components, leading to reduced performance, system instability, and premature failure. As processors and power densities have skyrocketed, traditional cooling methods like aluminum heat sinks and fans have reached their limits. The bottleneck is often not the heat sink itself, but the microscopic air gaps between the heat-generating component and the cooling solution. Air is a poor thermal conductor, and these gaps create significant insulating barriers. This is where a remarkable class of materials comes into play. Thermal conductive silicone has emerged as a fundamental engineering material, silently and efficiently enabling the thermal management that underpins our technological world.
What is Thermal Conductive Silicone?
At its core, thermal conductive silicone is a synthetic elastomer, a rubber-like material, that is engineered to possess high thermal conductivity while maintaining the beneficial properties of silicone. It is not a single compound but a carefully formulated composite.
Its structure consists of two primary parts:
- Silicone Polymer Matrix: This base provides inherent flexibility, high electrical insulation, resistance to extreme temperatures (typically from -50°C to over 200°C), and excellent environmental stability. It is resistant to moisture, oxidation, and many chemicals.
- Thermally Conductive Fillers: The silicone matrix itself is thermally insulating. To transform it into a conductor of heat, manufacturers load it with a high volume of fine ceramic or metal powder fillers. These fillers create percolation pathways within the silicone, allowing heat to travel through the material. Common fillers include aluminum oxide, boron nitride, zinc oxide, and in highly conductive grades, aluminum nitride or even silver. The type, size, shape, and concentration of these particles directly determine the thermal performance of the final product.
This combination results in a material that is both soft and conformable yet capable of effectively channeling heat away from sensitive components.
Key Properties and Advantages
The widespread adoption of thermal conductive silicone is due to a unique combination of properties that are difficult to find in any other single material.
- High Thermal Conductivity: Ranging from 0.5 W/mK to over 5.0 W/mK, these materials offer a significant upgrade over air (0.024 W/mK), effectively bridging the thermal gap between components and heat sinks.
- Electrical Insulation: Despite their excellent thermal conduction, most formulations are excellent electrical insulators, with high dielectric strength. This is a critical safety feature, preventing short circuits on densely packed printed circuit boards (PCBs).
- Conformability and Low Interface Resistance: Unlike rigid, solid materials, thermal conductive silicone is soft and compressible. It can conform to uneven surfaces, microscopic scratches, and imperfections on both the component and heat sink, displacing the insulating air and minimizing Thermal Interface Resistance (TIR). This intimate contact is the key to its efficiency.
- Flexibility and Resilience: The material can withstand stress, vibration, and thermal cycling without cracking, tearing, or permanently deforming. It maintains its sealing and thermal transfer properties over long periods under harsh conditions.
- Ease of Application: Available in pre-cured sheets (pads) or dispensable pastes (grease), it offers manufacturers versatility. Pads are clean and easy to handle for assembly, while pastes can be dispensed automatically for high-volume production and can fill larger, irregular gaps.
Common Forms and Applications
Thermal conductive silicone is versatile and comes in several forms, each tailored for specific applications across numerous industries.
Thermal Grease (Paste): This is a viscous, semi-liquid compound consisting of silicone oil filled with conductive particles. It offers the lowest thermal impedance because it can form an extremely thin layer, perfectly filling micro-imperfections.
- Applications: Primarily used between central processing units (CPUs)/graphics processing units (GPUs) and their heat sinks in computers, servers, and gaming consoles. It is the go-to material for achieving maximum thermal performance in high-power computing.
Thermal Gap Pads: These are solid, pre-cured sheets of thermal conductive silicone of varying thicknesses, softness (durometer), and conductivity. They are the workhorses of electronics thermal management.
- Applications: Used in smartphones to manage heat from processors and batteries; in solid-state drives (SSDs) to cool NAND flash memory; in power supplies and LED lighting assemblies to cool power transistors and regulators; and in electric vehicle battery packs and motor controllers. They provide both thermal transfer and mechanical cushioning.
Thermally Conductive Adhesives/Encapsulants: These are two-part systems that cure to form a rigid or flexible bond while conducting heat. They serve a dual purpose: mechanically attaching components and managing thermal performance.
- Applications: Permanently bonding heat sinks to PCBs without needing mechanical fasteners; potting and protecting sensitive power electronics modules from moisture, dust, and physical damage while dissipating the heat they generate.
The Critical Role in Advanced Technologies
The importance of thermal conductive silicone grows with every technological advancement.
- 5G Infrastructure: The high-frequency, high-power components in 5G base stations and antennas generate immense heat. Thermal conductive silicone pads and gap fillers are essential to maintain signal integrity and prevent downtime.
- Electric Vehicles (EVs): EV power inverters, onboard chargers, and battery management systems operate at very high currents and voltages. Efficient thermal management is not just about performance but about safety and battery longevity. Thermal conductive silicone materials are used throughout these systems to ensure heat is effectively spread to cooling plates and housings.
- High-Performance Computing (HPC) and AI: The server racks powering AI and cloud computing contain processors that can consume hundreds of watts each. Thermal conductive silicone grease and pads are fundamental in enabling the complex liquid and air cooling solutions required to keep these data centers operational.
Selection Considerations and Future Outlook
Choosing the right thermal conductive silicone requires balancing several factors: thermal conductivity needs, required softness for gap filling, electrical insulation requirements, environmental conditions (operating temperature, exposure to chemicals), and application method.
The future of thermal conductive silicone is focused on innovation to meet even greater demands. Research is ongoing into next-generation fillers like graphene and carbon nanotubes to achieve conductivities rivaling metals while maintaining electrical insulation. There is also a push towards non-silicone-based matrices for specific applications and improving the sustainability and ease of rework of these materials.
