Views: 6 Author: Site Editor Publish Time: 2021-04-14 Origin: Site
The thermally Conductive gel series product is a two-component pre-formed thermally conductive silicone grease product, which mainly meets the needs of low pressure and high compression modulus when the product is in use. It can realize automatic production and has good contact with electronic products during assembly. A low contact thermal resistance and good electrical insulation characteristics. This material has some advantages of thermal pads and thermal grease at the same time, which better compensates for the weaknesses of the two.
Thermally conductive gel inherits the good affinity of silicone materials, weather resistance, high and low temperature resistance, and good insulation. At the same time, it has strong plasticity and can meet the filling of uneven interfaces and meet the heat transfer needs of various applications. It has high thermal conductivity, low compression force application, low pressure, high compression ratio, high electrical insulation, good temperature resistance, and can realize automatic use.
Features of thermally Conductive gel
1. Performance characteristics
Compared with the thermal pad, the thermal gel is softer and has better surface affinity. It can be compressed to a very low thickness, so that its heat transfer efficiency is significantly improved, and the minimum can be compressed to 0.1mm. At this time, the thermal resistance can be At 0.08℃·in2/W-0.3 ℃·in2/W, the performance of some silicone grease can be reached. In addition, the thermally conductive gel has almost no hardness and will not cause internal stress to the device after use.
Thermally conductive gel is easier to handle than thermally conductive silicone grease. The general use of silicone grease is screen or steel plate printing, or direct brushing, which is very unfriendly to users and the environment, and because of its flowability, it is generally not used for occasions with a thickness of 0.2mm or more.
The thermally conductive gel can be kneaded into any desired shape, ensuring good contact for uneven PCB boards and irregular devices (such as batteries, component corners, etc.).
Thermally conductive gel has a certain degree of adhesion, and there will be no problems with oil and drying, and it has certain advantages in reliability.
2. Advantages of continuous operation
The thermal gel can be directly weighed and used. The commonly used continuous use method is a dispenser, which can realize fixed-point and quantitative control, which saves labor and improves production efficiency.
3. How to use thermal gel
When using manual thermal glue, you need to unscrew the mouth cover, connect the threaded mixing head, and then clamp the hose to the bayonet of the AB glue gun, and apply the glue forcefully. The AB glue is squeezed out by the glue gun to the mixing head and guided by the thread Complete the uniform mixing (A/B two colors are mixed into a uniform color), and finally according to the heat dissipation structure design, the uniformly mixed thermally conductive glue is dotted to the heating position. For the dispensing type, follow the instructions of the dispenser.
4. Curing time
From the contact between the A and B glue mixing heads, the viscosity will increase in 5 minutes, dry in 10 minutes, and 30 minutes to 3 hours, the product will gradually harden and become elastic, showing that the hardness continues to rise to no longer change.
The cured thermal gel is equivalent to thermal silica gel, with good high temperature resistance and aging resistance, and can work for a long time at -40~150℃.
6. Pay special attention
Thermally conductive gel is different from adhesive glue, its adhesive force is relatively weak, and it cannot be used to fix the heat sink
Applications of thermal gel
Thermally conductive gel is widely used in LED chips, communication equipment, mobile phone CPUs, memory modules, IGBTs and other power modules, power semiconductors and other fields.
In order to pass the UL certification for the exported LED lights, most manufacturers use two-component potting glue for potting.
The lights exported to the United States require a 50,000-hour warranty. The quality of the current LED lights is no problem. The main fault is the power supply. The power supply after potting with potting glue cannot be removed, only the whole lamp Perform scrap replacement.
If the power supply is partially filled with thermally conductive gel, the heat can be effectively exported, and the power supply can be easily replaced if there is a problem with the power supply, thereby saving costs for the enterprise.
Of course, for lamps that require waterproofing, since thermal gel cannot fill all the gaps and gaps like potting glue, it cannot be waterproof and moisture-proof, and potting glue is still needed.
Another typical application is in LED fluorescent tubes. For the design of the power supply at both ends, in order not to occupy the size of the tube too much, the space of the two power supplies is relatively small, and the power of the 1.2m LED fluorescent tube is usually designed to be 18w to 20w, so that the heat generated by the drive power supply becomes relatively large.
The thermal gel can be filled into the gap of the power supply, especially attached to the power device to help dissipate heat and extend the life of the lamp tube. For some sealed modular power supplies, thermal gel can be used for partial filling to achieve the effect of heat conduction.
Next is the heat dissipation of the chip. This method should be familiar to everyone. The silicone grease layer between the processor and the heat sink is a principle, and its function is to allow the heat emitted by the processor to be transferred to the processor faster The radiator thus radiates.
Similarly, thermal gel can also be applied to mobile phone processors. A thermal conductive gel heat sink similar to silicone grease is used on the processor of Huawei mobile phones. This is more effective than just attaching a graphite heat dissipation film. Heat conduction will be faster.