Phase change wafer, silicone grease and liquid gold: the advantages and disadvantages of three kinds of thermal conductive materials and the analysis of application scenarios

In the heat dissipation system of electronic equipment, the contact surface between the processor (CPU, GPU) and the heat sink is not completely flat, and if it is directly attached, there must be a small gap. These tiny air layers will greatly reduce the heat conduction efficiency, so it is necessary to fill the heat conduction material to enhance the heat transfer. Common thermal conductive materials are phase change, silicone grease and liquid metal (liquid gold).
Although they all bear the role of "bridge", they are different in performance, stability and difficulty of use.

2. phase change sheet: stable and durable "fool type scheme"

definition and principle
A phase change sheet is a heat transfer medium that undergoes a phase change (solid → semi-liquid) when heated. When installed, it is a solid sheet, which is easy to fit; when the equipment heats up, it will soften and fill the gap, thereby improving the heat conduction effect.

Advantages

Installation is simple: like sticking tape, there is almost no use of the threshold.

Clean and tidy: It will not stain the equipment like silicone grease, and there is no need to worry about liquid gold spillover.

Long life: not easy to dry or volatile, suitable for long-term use.

Disadvantages

Thermal conductivity in general: thermal conductivity (about 2~6 W/m · K) is lower than high-end silicone grease, more can not be compared with liquid gold.

A certain temperature activation is required: On low-power devices, the phase change effect may not be obvious.

Applicable Scenarios
Suitable for office computers, notebooks, home appliance main control chips and other heat dissipation requirements are not extreme, but pay attention to stability and maintenance-free scenes.

3. silicone grease: the most cost-effective "evergreen tree"

definition and principle
Silicone grease is a kind of silicone oil as the matrix, doped with oxide metal powder thermal paste body. Its fluidity can fill the microscopic gap and reduce the air insulation layer.

Advantages

Moderate thermal conductivity: thermal conductivity is generally 5~12 W/m · K, and some high-end products can reach 14 W/m · K.

Widely used: almost all DIY players and manufacturers will use silicone grease as the default solution.

Low cost: tens of dollars to buy a, can be used many times.

Disadvantages

Aging: After long-term high temperature use, the silicone grease may dry or pump out (squeezed to the edge), affecting heat dissipation.

Requires maintenance: It is usually recommended to replace it once every 1 to 2 years.

Use a little messy: uneven or too much will get the motherboard, capacitor and other parts.

Applicable Scenarios
Suitable for most desktop CPU/GPU, gaming notebook, is the most balanced choice.

4. liquid gold: the "weapon" of extreme heat dissipation"

definition and principle
Liquid metal (referred to as liquid gold) is a kind of gallium, indium as the main components of the alloy, at room temperature to maintain liquid, thermal conductivity can be as high as 70~80 W/m · K, is several times the grease.

Advantages

Extremely strong thermal conductivity: can significantly reduce the core temperature, part of the CPU can cool 5~15 ℃.

Good long-term stability: not easy to dry, there is no silicone grease pump out of trouble.

Disadvantages

Strong conductivity: Once leaked into the circuit, it may cause a short circuit, and the risk is extremely high.

Erosiveness: Liquid gold will react chemically with aluminum and must be matched with a copper or nickel-plated base radiator.

The use of high threshold: need to be careful to apply, control the dose, to avoid spillage.

Applicable Scenarios
Commonly used in high-end players overclocking, servers, fever-level game books, the pursuit of extreme heat dissipation of the crowd.

5. three comparison table

6. selection recommendations

Figure worry-free users: select phase change films, maintenance-free, and forget when installed.

The pursuit of balance players: choose silicone grease, cost-effective, heat dissipation and operation are more balanced.

Fever overclocking enthusiasts: select liquid gold, can squeeze hardware performance, but must be well protected.

7. epilogue

Phase change chips, silicone grease, and liquid gold all seem to be thermally conductive materials, but they correspond to completely different usage scenarios. Just like buying a car, some people pursue fuel consumption (phase change chip), some people pursue cost performance (silicone grease), and some people pursue extreme performance (liquid gold).
The selection of the heat dissipation material can not only ensure the stable operation of the hardware, but also extend the life. If you are just a daily office, there is no need to risk liquid gold; and if you are an enthusiast, liquid gold can really let you experience the pleasure of "performance release.