Thermal conductive gel and its application

Thermal conductive gel is a gel shaped thermal conductive material made of silica gel composite thermal conductive filler after stirring, mixing and packaging. This material has some advantages of both thermal pads and thermal grease, which better compensate for the weaknesses of both.

The thermal conductive gel inherits the advantages of silica gel material, such as good affinity, weather resistance, high and low temperature resistance, and good insulation. At the same time, it has strong plasticity, can meet the filling of uneven interfaces, and can meet the heat transfer requirements in various applications.

Characteristics of thermal conductive gel

1. Performance characteristics

Compared with the thermal conductive gasket, the thermal conductive gel is softer and has better surface affinity. It can be compressed to a very low thickness, which significantly improves the heat transfer efficiency, and can be compressed to a minimum of 0.1mm. At this time, the thermal resistance can be 0.08 ℃ · in2/W -0.3 ℃ · in2/W, which can reach the performance of some silicone grease.

Thermal conductive gel is easier to operate than thermal conductive silicone grease. The general use of silicone grease is screen printing or steel plate printing, or direct brushing, which is very unfriendly to users and the environment. Due to its certain fluidity, it is generally not suitable for occasions with a thickness of 0.2mm or more.

And the thermal conductive mud can be formed into any desired shape, ensuring good contact for uneven PCB boards and irregular components (such as batteries, component corners, etc.).

The thermal conductive gel has certain adhesiveness, and will not produce oil or become dry, so it has certain advantages in reliability.

2. Advantages of Continuous Homework

The thermal conductive gel can be directly weighed for use. The common continuous use mode is the dispensing machine, which can achieve fixed point quantitative control, save labor and improve production efficiency.

Applications of thermal conductive gel

Thermal conductive gel is widely used in LED chips, communication equipment, mobile phone CPUs, memory modules, IGBT and other power modules, power semiconductor fields.

The application is in the driving power supply of LED bulb lights. In order to obtain UL certification for exported LED lights, manufacturers often use two-component potting adhesive for potting. Lights exported to the United States require a 50000 hour warranty, and currently the quality of LED chips is not a problem. The main fault is the power supply, which cannot be disassembled after being sealed with sealant and can only be scrapped and replaced as a whole. If thermal conductive mud is used to locally fill the power supply, it can effectively dissipate heat, and if there are problems with the power supply, it can be easily replaced to save costs for the enterprise. Of course, for lamps that require waterproofing. Because thermal conductive mud cannot fill all gaps like sealant, it cannot achieve waterproofing and moisture resistance, so sealant still needs to be used.

Another typical application is in LED fluorescent tubes, where the power supply is placed at both ends. In order to minimize the size of the tube, the space for the two power supplies is relatively small. However, the power of a 1.2-meter LED fluorescent tube is usually designed to be 18W to 20W, which increases the heat generation of the driving power supply. Thermal conductive mud can be filled into the gaps of the power supply, especially attached to power devices to help dissipate heat and extend the life of the lamp tube. For some sealed module power supplies, thermal conductive mud can be used for local filling to achieve thermal conductivity.

Next is the heat dissipation of the chip. As for this method, everyone should be familiar with it. The silicon grease layer between the processor and the heat sink is based on the same principle, which allows the heat emitted by the processor to be quickly transferred to the heat sink and dissipated.