Thermal gap fillers are a type of thermal interface material that is used to fill gaps between two surfaces to improve heat transfer. They are typically made of a soft, compliant material, such as silicone or urethane, that conforms to the surfaces it is placed between.
These materials provide unrivaled thermal and mechanical performance while inducing virtually zero stress on electronic components during assembly, helping you improve performance and reliability across your device assemblies.
Because they’re liquid mediums, thermal gap filler materials can conform to highly intricate topographies and multi-level surfaces. This allows them to deliver better wet-out for optimized thermal resistance, generally lower than more solid pad-based mediums.
Application volume and pattern are completely adaptable to suit a wide range of applications.
Thermal Gap Filler Description
When the advancement of thermal interface materials is limited by the trade-off between thermal conductivity, hardness, and processability, we have achieved a new level of performance by combining high thermal conductivity and high flexibility through multiple technological innovations.
Our thermal silicone pads utilize independently developed organic silicone resin and a special interpenetrating network structure. By avoiding the addition of low-molecular-weight silicone oils, the material's hardness is reduced. This allows for a high filling ratio with high-molecular-weight molecular structures while maintaining flexibility through the presence of small-molecular-weight network structures. This improves the material's heat resistance and durability while minimizing the risk of exudation.
The OSiTC-A36 is designed to replace the Tflex-HD90000 and can be adjusted according to the customer's test situation and requirements. OSiTC-A36 is the latest product in our High Deflection series. OSiTC-A36 combines 9.5 W/mK thermal conductivity with superior pressure versus deflection characteristics. The combination will allow minimal stress on components while also yielding low thermal resistance. As a result, less mechanical and thermal stresses will be experienced within your device.
Contact Us for further assistance with thermal gap filler pads and related thermal interface materials.
Features and Benefits of Thermal Gap Filler
• 9.5 W/mK thermal conductivity
• Low pressure versus deflection
• Excellent surface wetting for low contact resistance
• Minimizes board and component stress
• Low Outgassing
• Large tolerance applications
• Environmentally friendly solution
Thermal Gap Filler Specifications
We have also developed a technology that combines boron nitride with alumina, which significantly enhances thermal conductivity. By utilizing the synergistic effects of plate-like boron nitride and spherical alumina, the amount of alumina required can be reduced, resulting in reduced product density.
Additionally, we have developed a compression molding process technology that enables the production of ultra-soft pads, which can be used in certain applications as alternatives to thermal silicone grease.
| Product Code | Performance | Thermal conductivity (W/m.k) | Density (g/cm³) | Hardness (shore 00) |
| OSiTC-A36 | High thermal conductivity, and low hardness | 9.5 | 3.59 | 40 |
| OSiTC-A36BN | Strengthen high thermal conductivity | 12 | 3.63 | 70 |
| OSiTC-A20BN | High thermal conductivity, and low density | 8 | 3.33 | 65 |
| OSiTC-SF18 | Super soft | 7 | 3.0 | <10 |
All models of thermal silicone pads are made of metal oxides and boron nitride, without any metallic components, providing insulation and flame retardancy. Compare prices.
This product manual is the basic information. and product performance improvements, product specifications, etc. are subject to change without notice. Our company guarantees that the products meet the specifications, but due to the differences in the customer's use conditions and the process is not under the control of our company, the customer must test it first to confirm whether it is suitable for your application. The performance parameters of the products can be adjusted according to the customer's requirements.
Available in various shapes, sizes, and thermal conductivities, thermal gap fillers offer a cost-effective solution for some of the most difficult and delicate thermal situations in a broad spectrum of applications. Get in touch today to discuss your specific needs.
Thermal Gap Fillers Applications:
Thermal Gap fillers are used in many applications, thanks to their diversity and flexible dispensation. In the modern world of electronics, gap fillers can be used in many electronic components, including:
Printed circuit boards (PCBs)
Power supply cooling
High volume applications where automatic dispensing can be used
Where pad configurations are not suitable
Where potting compounds can be used
Across varied topographies and surfaces
In gaps higher than 0.5mm, to eliminate voids
OSI Thermal Gap Fillers can be used across many electronic applications and industries. Explore all our liquid gap fillers and find the one that is right for your application.
Why Choose OSI Thermal Gap Fillers?
1. Ultra-low modules for minimal stress during assembly
Because thermal gap fillers are dispensed and wet-out in a liquid state, the materials will create virtually zero stress on components during the assembly process. Thermal gap fillers can be used to interface even the most fragile and delicate devices.
2. Excellent conformability to intricate geometries
Liquid gap filler materials can conform to intricate topographies, including multi-level surfaces. Due to their flowability before cure, gap fillers can fill small air voids, crevices, and holes. This reduces the overall thermal resistance to the heat-generating device.
3. Single solution for multiple applications
Unlike pre-formed gap filling materials, thermal gap fillers offer infinite thickness options and eliminate the need for specific pad thicknesses or die-cut shapes for individual applications.
4. Efficient material usage
Manual or semi-automatic dispensing tools can be used to apply liquid thermal gap filling materials directly to the target surface, resulting in efficient use of material with minimal waste. Further material volume optimization can be achieved with the implementation of automated dispensing equipment, which allows for precise material placement and reduces the material application time.
5. Customizable flow characteristics
Although thermal gap fillers are designed to flow easily with minimal pressure, they are thixotropic, which helps the material remain in place after dispensing and before cure. OSI gap filler offerings include a range of rheological characteristics and can be tailored to meet your flow requirements. This includes self-leveling and highly thixotropic materials that maintain their form as dispensed.
Thermal Gap Fillers FAQs
1. What are Thermal Gap Fillers?
Thermal gap fillers are valuable aids as electronic component heat dissipation materials because of their thermal conductivity properties. They fill spaces and replace the air from them. Air is a poor conductor of heat. Aided by their thermal conductivity properties, gap fillers are scientifically engineered to increase overall heat transfer inside a device or system. They keep components cooler and within allowable thermal ranges.
2. How do Liquid Gap Fillers Work?
The liquid material fills the gap between the hot component and the heatsink by flowing between the two components and making sure no air or void will remain between them.
3. What's the difference between gap fillers and thermal gap pads?
● Gap fillers are often applied by meter-mixing a two-part system, dispensing on one of the two substrates, and pressing the two substrates together to reach a specified thickness. The material is then allowed to form a solid, but compliant interface. Thermal pads, on the other hand, are pre-cut to the desired shape, applied to one substrate, compressed down to set thickness, and fixed in place.
● The applied compressive load forces the solid, yet compliant, pad to make intimate contact with the rough surfaces. Also, gap fillers, unlike solid thermal pads, flow into the small valleys and create more intimate contact with the surface. This allows a more efficient transfer of heat between the upper and lower substrates.
● When comparing the key attributes of the two types, the relative cost of using thermal pads is high due to the costly scrap that results. Air entrapment is more frequent with thermal pads since they can’t reach those tiny spaces that result from surface roughness. Gap fillers are the answer for design flexibility since the hardness and working time can be adjusted using the mix ratio of the gap filler’s two parts. Lastly, when it comes to applying the product, the large form factor thermal pads can be difficult to apply without trapping air, and automation is difficult. On the other hand, gap fillers are well-suited for high-volume production.
4. What are the Common Uses of Thermal Gap Fillers?
Thermal Gap Fillers are used widely to help resolve heat mitigation issues in electronic devices. Some of the industries and products utilizing gap fillers are automotive ADAS, automotive lighting, infotainment and powertrain, drones/satellites, gaming systems, instrumentation, notebooks/tablets, portable devices, routers, smart home devices, test and measurement equipment, and wireless infrastructure.
5. How do you increase the cure speed of a thermal gap filler?
To increase the cure speed of most gap fillers, potting materials, and/or adhesives, increase the temperature of the part to which the materials are applied. This can be done using an oven, a heat lamp, or induction heating. Parts can be pre-heated to the desired temperature, or material can be dispensed first, and then the part can be heated. It is a general rule of thumb that the cure speed will approximately double for every 10-degree Celsius increase in temperature.
It is worth noting that, for rigid materials, increasing cure speed can increase the risk of generating high internal stress in the material, which may degrade its mechanical strength and its ability to resist thermal and/or mechanical shock.
