What Is Thermal Grease?

Thermal grease is commonly known as thermal grease, also known as thermal paste. Thermal grease is made of silicone as the main raw material, adding materials with excellent heat resistance and thermal conductivity, and made of thermal grease-like compound for power amplifiers , transistors, tubes, CPU and other electronic components heat conduction and heat dissipation, so as to ensure the stability of the electrical performance of electronic instruments, meters and so on.

Thermal grease is a kind of material used to fill the gap between the CPU and the heat sink, which is also called thermal interface material. Its function is to conduct the heat emitted by the CPU to the heat sink, keep the temperature of the CPU at a level that can work stably, prevent the CPU from being damaged due to poor heat dissipation, and prolong its service life.

In thermal management applications, even two flat surfaces with very smooth surfaces can have voids when they come into contact with each other. The air in these voids is a poor conductor of heat and hinders the conduction of heat to the heat sink. Thermal grease is a material that can fill these voids and make heat conduction more smoothly and quickly.

Since thermal grease is a chemical substance, it also has relevant performance parameters that reflect its own working characteristics. As long as we understand the meaning of these parameters, we can judge the performance of a thermal grease.

Thermal conductivity

The thermal conductivity of thermal grease is basically the same as that of the radiator. Its unit is W/mK, that is, the temperature difference of a cylinder with a cross-sectional area of ​​1 square meter along the axial distance of 1 meter is 1 Kelvin (1K=1℃). heat transfer power. The larger the value, the faster the heat transfer rate of the material and the better the thermal conductivity. At present, the thermal conductivity of Novotel thermal grease can reach 5.2W/m.K.

Thermal resistance coefficient

The thermal resistance coefficient expresses the effect of an object on the conduction of heat. The concept of thermal resistance is very similar to that of resistance, and the unit is also similar (℃/W), that is, the temperature difference between the two ends of the heat conduction path when the continuous heat transfer power of the object is 1W. Obviously, the lower the thermal resistance, the better, because under the same ambient temperature and thermal power, the lower the thermal resistance, the lower the temperature of the heating object. The size of the thermal resistance has a great relationship with the material used in the thermal grease.

At present, the thermal resistance coefficient of mainstream thermal grease is less than 0.1°C/W, and the excellent ones can reach 0.005°C/W.

Operating temperature

Due to the characteristics of silicone grease itself, its operating temperature range is very wide. The working temperature is an important parameter to ensure that the thermal conductive silicone grease is in a solid or liquid state. If the temperature is too high, the volume of the thermal silicone grease will expand, the intermolecular distance will increase, the interaction will weaken, and the viscosity will decrease; if the temperature decreases, the fluid volume will shrink and the intermolecular distance will be reduced shortening, the interaction is strengthened, and the viscosity increases, both of which are not conducive to heat dissipation.

The working temperature of thermal grease is generally -40℃~200℃. We don’t need to worry about the working temperature of thermal grease, after all, it is difficult to exceed the temperature of CPU/GPU by conventional means.

Viscosity

Viscosity is a measure of fluid viscosity, which refers to the resistance to flow inside the fluid, expressed by the ratio of the shear stress to the fluid and the shear rate. There are many ways to measure viscosity. For example, the unit of dynamic viscosity is Pa. ·second.
For thermally conductive silicone grease, the viscosity is about 2500 Pa·s, and it has good tiling properties. It can be easily tiled around the surface of the chip under a certain pressure, and a certain viscosity is guaranteed, so that it will not become too thick after extrusion. Excess grease will flow.

Dielectric constant

Dielectric constant is used to measure the performance of insulators to store electrical energy, which refers to the ratio of the capacitance between two metal plates when insulating material is used as the medium to the capacitance between the same two plates when air is used as the medium or vacuum. The dielectric constant represents the degree of polarization of the dielectric, that is, the binding ability to charge. The larger the dielectric constant, the stronger the binding ability to charge.

Ordinary thermal grease uses materials with good insulation, but some special silicone greases (such as silver-containing silicone grease, etc.) may have a certain degree of conductivity. The dielectric constant of air is about 1, and the dielectric constant of common thermal grease is about 5.

Oil separation

Oil separation refers to the precipitation amount of silicone oil after the thermal grease heat-dissipating paste is kept at 200 ℃ for 24 hours, and it is an index to evaluate the heat resistance and stability of the product. Apply the silicone grease heat-dissipating paste on the white paper for observation, and you will see the phenomenon of oil seepage. If the oil separation is high, the oil separation phenomenon is obvious; or open the container containing silicone grease for a long time. Obvious oil separation is seen on the surface of the silicone grease or around the container.

There are many types of silicone greases on the market today, and different parameters and physical properties determine different uses. Thermal grease is a kind of high thermal conductivity insulating silicone material, which is almost never cured, and can maintain the grease state when used for a long time at the temperature of -40℃-200℃. Thermal grease thermal paste has excellent electrical insulation, excellent thermal conductivity, low oil separation (tends to zero), high and low temperature resistance, water resistance, ozone resistance, and weathering resistance. Thermal grease heat dissipation paste can be widely applied to various electronic products, between the heating body (power tube, thyristor, electric heating stack, etc.) and heat dissipation facilities (heat sink, heat dissipation strip, shell, etc.) in electrical equipment The contact surface acts as a heat transfer medium, and has the properties of moisture-proof, dust-proof, anti-corrosion and shock-proof. Thermal grease heat-dissipating paste is suitable for surface coating or overall potting of various microwave devices such as microwave communication, microwave transmission equipment, microwave special power supply, regulated power supply, etc. This kind of silicon material provides excellent heat-generating electronic components. Thermal conductivity.

How To Apply Thermal Grease?

Thermal grease, also known as thermal conductive grease, thermal paste, or thermal compound, etc., is used to create a thermally conductive layer between the processor and the heat sink. Thermal grease is the link between the cpu and the radiator for heat transfer. It also acts as a heat transfer medium, increases the contact area, buffers vibration and pressure, and fills the pits between the radiator and the cpu. Since thermal grease conducts heat better than air, applying thermal grease between the processor and the heat sink can enhance heat transfer from the processor to the heat sink.

After the influence of the thickness of silicone grease on heat dissipation, the CPU temperature fluctuates between 61-62°C when applying an appropriate amount of silicone grease, and the CPU temperature fluctuates between 63-64°C when a large amount of silicone grease is applied. It can be found that the thickness of the silicone grease layer has an obvious effect on heat dissipation. From this test, there is a 2°C gap between the two.

Therefore, the correct application of thermal grease has a multiplier effect on the heat dissipation of the cpu. Too much or too thick thermal grease is equivalent to adding a heat-conducting medium, which affects the heat transfer of the cpu to the radiator (the heat of the thermal grease the resistance is larger than the thermal resistance of metal), and excess heat dissipation silicone grease will even flow into the CPU socket. Although the current silicone grease is generally insulating and will not cause a short circuit, it flows to the metal contacts of the CPU and the socket. It is easy to cause a short circuit between the cpu pins. In the light of the computer can not be started, in severe cases, it will cause damage to the cpu or other peripheral hardware; too little or uneven application of thermal grease will cause no gap between the cpu and the radiator. The medium of buffering and heat conduction reduces the contact area between the CPU and the heat sink in disguised form, resulting in a decrease in heat dissipation efficiency.

Process plan for applying thermal grease

  1. First clean the surface of the CPU core and the bottom of the heat sink with a high-purity solvent (such as high-purity isoamyl alcohol or acetone) and a lint-free cloth (such as a camera lens cloth), taking care not to let your fingers touch the surface of the core and heat sink.
  2. Determine the area on the heat sink that is in contact with the CPU, and apply an appropriate amount of thermal grease on the CPU. At this time, you can ignore its uniformity, coverage and thickness.
  3. Prepare a moderately soft and hard plastic scraper (or cardboard), spread the thermal grease, and use the scraper to scrape in one direction at an angle of about 45 degrees, so that the thermal grease is evenly formed on the entire surface of the CPU. thin layer.
  4. Apply a small amount of thermal grease to the bottom of the radiator. Similarly, using the method we just applied to the CPU, apply the thermal grease to an area as large as the CPU shell. The purpose of this step is to make the particles in the thermal grease fully Fill the uneven grooves on the bottom of the radiator to make sure that there are no foreign objects on the surface of the radiator base and the CPU core, then install the radiator on the cpu, and fasten the fasteners.

Matters needing attention after applying thermal grease

  1. The heat-dissipating silicone grease will never be cured after being applied. It should be noted that if the heat-dissipating silicone grease is cured, this heat-dissipating silicone grease is unqualified and cannot be used in industrial manufacturing in large quantities. When buying, you need to pay attention. In order to avoid this situation, users can buy products with word-of-mouth guarantee, which can reduce the chance of this situation. For example, Nuofeng Electronics nfion, which focuses on the R&D and customized production of heat-dissipating silicone grease, can provide different customized solutions.
  2. Apply evenly: For the bottom surface of an ordinary radiator, the thickness of thermal grease applied is about the thickness of a piece of paper. After the thermal grease is applied, place the heat sink on the CPU. At this time, it can only be pressed lightly, and the heat sink cannot be rotated or translated. Otherwise, the thickness of the thermal grease between the heat sink and the CPU may be uneven.
  3. It is necessary to observe whether there are air bubbles after applying the heat-dissipating silicone grease. If there are air bubbles, they can be punctured with a toothpick. Otherwise, these air bubbles will cause uneven application. In addition, there will be air in the air bubbles, which will also increase the thermal resistance and affect heat dissipation. Effect.
  4. The remaining heat dissipation silicone grease needs to be sealed and can be placed in a cool place, so that it can be used up within 12 months. After more than 12 months, the thermal conductivity will decrease and cannot be used again.

Thermal grease is a thermally conductive material with good heat dissipation performance. Thermal grease can be used in various electrical appliances or electronics. There is no change in performance before and after use, and it is always in the state of grease. Thermal grease can only be smeared in the middle of the heating element of the electrical appliance and the heat dissipation facility. Only by mastering the correct operation method when smearing can achieve the purpose of heat dissipation.

Why Do High-Power Led Lamps Need To Be Coated With Thermal Grease?

As an excellent semiconductor optoelectronic device, LED has been unanimously recognized in the market for its advantages of small size, low power consumption, long service life and environmental protection, and has become a new generation of ideal solid-state energy-saving lighting sources.

High-power LED packaging has been a research hotspot in recent years due to its complex structure and process, which directly affects the performance and life of LEDs.

However, with the development of LEDs with high light intensity and high power, the problem of heat dissipation has become increasingly prominent, which seriously affects the light output characteristics of LEDs and the life of the device, and has become a key problem that must be solved in high-power LED packaging. The root cause of the heat dissipation problem of LED is the high power density of the chip, and the heat dissipation efficiency of the chip has not been improved in time.

Heat dissipation is a key problem for LED lamps to solve, and a heat conduction process before this is even more critical. The LED chip will generate a lot of heat when it is working. If it cannot be dissipated quickly and efficiently, the LED chip with too high junction temperature will seriously affect its own service life. At present, there are quite effective means to improve the heat dissipation capacity of LED lamps. We can coat a layer of thermal grease between the LED aluminum substrate and the aluminum heat sink to reduce the thermal resistance of the contact surface between them, thereby improving its own thermal conductivity. heat dissipation capacity.

Why apply a layer of thermal conductive silicone grease to improve the heat dissipation performance of LED lamps? Because the main heat dissipation method of LED lamps is to dissipate heat through the LED radiator. The same is true for the heat generated by the LED chip. The LED chip will first conduct the heat to the aluminum substrate, and then the aluminum substrate will conduct the heat to the aluminum heat sink. However, the aluminum substrate is often fixed on the aluminum heat sink by screws. The structure fixed in this way often forms an air gap between them, and the thermal resistance of the air is very large, which is higher than other thermal resistances. It is dozens of times larger, so it is necessary to apply thermal grease to fill the gap to increase the area of ​​the contact surface, thereby increasing the heat flux, reducing the thermal resistance, and improving the heat dissipation performance of the LED lamp.

In fact, the quality of heat dissipation depends on the material of the heat sink. Thermal grease thermal paste is a thermal medium, the better the thermal conductivity, the more heat is exported, and the better the cooling effect.

Does Thermal Grease Conduct Electricity? Thermal Grease and Conductive Grease You Must Know

Recently, a customer asked me, will the thermal grease on the LEDs, small household appliances, high-power lamps, etc. that we often use conduct electricity? In fact, this customer should be a layman. First of all, the correct answer is “thermal grease is non-conductive”. Because thermal grease is a high thermal conductivity insulating silicone material.

In addition, because silicon is insulating, insulating things must be non-conductive. We can think about the computers, TVs, mobile phones, chargers, LED lights and other related electrical products used in daily life. Thermal silicone is all insulating. If it is conductive, we will definitely be dangerous when using it. Therefore, when choosing thermal grease, we must choose a regular thermal grease with technical information, product test reports, and material safety. information, so that we can use it with confidence.

Sometimes it is easy for users to confuse thermal grease with conductive grease, thinking that thermal grease can also play a conductive role, so users should distinguish the difference between the two when inquiring about products. The following is a thermal grease manufacturer, CoolThermo, to introduce the difference between thermal grease and conductive grease.

Thermal Grease

Thermal grease is a kind of silicone grease, which is made of thermal grease-like compound by adding materials with excellent heat resistance and thermal conductivity. Thermal grease has good thermal conductivity and excellent insulation properties, and insulation is non-conductive. High-conductivity thermal grease can quickly transfer heat from electronic components.
Thermal grease is mainly used for: cpu fans, LED lights, ceramic sheets for hair straighteners, heating pipes, radiators, transistors, electronic tubes, water dispensers (ice galls), coffee machines, etc.

Conductive grease

Conductive grease is also a kind of silicone grease, also known as conductive paste. It is made of compound soap thickened ketone synthetic oil and added with special conductive additives. Conductive grease is conductive, non-corrosive, moisture-proof, thermally stable, non-toxic, Odor and other properties, has good high and low temperature performance, anti-rust and anti-discoloration properties and excellent compatibility with thermoplastics.
Conductive grease is used for electronic components and different types of metals that require electrical conductivity and anti-static performance to prevent galvanic corrosion; electrical switches, electronic contact sheets, and connectors are lubricated, improve contact conductivity, increase service life, and prevent Carbide buildup at joints.

Generally speaking, the thermal conductivity of non-metallic fillers commonly used in silicone grease is 2.0~3.0W/m·K, while the thermal conductivity of metal materials can easily reach more than 300. By adding metal powder to increase the thermal conductivity of thermal grease will be very good. However, correspondingly, because the metal has electrical conductivity, the insulating performance of the thermal grease with silver powder is very poor, and it cannot be used for some applications with insulation requirements.

How To Test The Viscosity Of Thermal Grease?

Thermal grease is widely used in electronic and electrical, household appliances, medical equipment, security equipment, aerospace, instrumentation, lighting and other industries, and is an indispensable thermal conductive material. The function is simply to prolong the service life of the product. If the viscosity of thermal grease is not suitable for application, inconvenient operation and abnormal adhesion will occur during the application process, so how to identify the viscosity of thermal grease? Today, CoolThermo Technology, a thermal grease manufacturer, will introduce several methods for testing the viscosity of thermal grease.

Vertical flow

Vertical flow refers to the state in which the thermal grease flows vertically. The method of judgment is visual inspection. This method is very easy to identify and convenient for thermal grease with a large difference in viscosity, but for thermal grease with similar viscosity, This method may not be applicable and may lead to misjudgment. Therefore, the viscosity of thermal grease is only suitable for products with low viscosity, and the viscosity of contrast is only suitable for thermal grease with a large difference.

Viscosity

Can the viscosity of thermal grease be fully characterized by viscometer test? Thermal grease without special functions, generally the higher the viscosity, the greater the data measured by the viscometer, so using the viscometer to test the viscosity of the thermal grease can identify the viscosity of the thermal grease, but it has special functions For products with thixotropic properties, it may be inaccurate to use viscosity to identify the viscosity. Therefore, the premise of using the viscosity to identify the viscosity of thermal grease is to understand the functional characteristics of thermal grease.

Cone penetration

Penetration is an important indicator to identify the viscosity of thermal grease, and it is also a very effective method. The test of penetration of thermal grease is not affected by thixotropy, and is determined by the depth of the cone as a free-fall needle into the thermal grease. , The higher the viscosity of the thermal grease, the shallower the depth of the cone penetration. The key to the penetration test is to test the flatness of the needle penetration surface of the product.

The above methods to identify the viscosity of thermal grease need to be selected according to the functional characteristics of thermal grease itself. Among the three methods, CoolThermo Technology recommends using a cone penetration tester for testing.

How to choose high-quality high-temperature thermal grease?

Thermal grease, also known as thermal paste, is a paste made of special silicone oil as base oil, new metal oxide as filler, mixed with various functional additives, and processed by a specific process. The color is different due to different materials. Appearance.

Thermal grease has good thermal conductivity, temperature resistance and insulation properties. It is an ideal dielectric material for heat-resistant devices, and its performance is stable. It will not generate corrosive gas during use and will not affect the metal in contact. Therefore, thermal grease is widely used in electrical and electronic, household appliances, medical equipment, security equipment, aerospace, instrumentation, lighting and other industries; then, how to choose a thermal grease with stable quality is a difficulty that many users often encounter , Today, the thermal grease manufacturer will introduce to you several criteria for judging high-quality thermal grease.

Fineness

Whether the fineness of thermal grease is superior can be identified from several aspects, such as uniform colloid, bright chromaticity, easy operation, no coarse ore particles in the colloid and other surface phenomena, so the selection of thermal grease appearance indicators and operability are the judgments. The first step in the quality of thermal grease; if the colloid of thermal grease is uneven, some parts are thin, some parts are thick or difficult to operate uniformly, it will lead to a decrease in heat dissipation effect, so the fineness of thermal grease is very important.

low oil separation

Oil separation is a guide for the precipitation of silicone oil after the thermal grease is kept at a specific temperature for a certain period of time, and is an index to evaluate the stability of thermal grease. Many users have found that some thermal greases have a layer of oil on the upper layer after being used for a period of time, indicating that these thermal greases are relatively poor in terms of storage stability. If there is no special process for stirring and dispersing, the heat dissipation of the product and the operation Sex will decrease.

High heat resistance

The heat resistance of thermal grease refers to the fact that the thermal grease can still maintain its excellent performance under the condition of heat and maintain a longer service life. We all know that products that can generally use thermal grease are used in high temperature environments. Environment, the better the heat resistance of thermal grease, the more durable it will be.

When purchasing thermal grease, it should be noted that only those with good fineness and low oil separation are of good quality. In addition, thermal grease is a kind of heat dissipation material that needs to be used in the manufacture of many electrical appliances. High and low temperature change performance can be better used in more fields.

What Brand Of Thermal Grease Is Good? What Is The Thermal Conductivity? How To Choose High Quality Thermal Grease?

Thermal grease is a spacer material that fills the heat source and the heat sink. Its function is to transmit the heat emitted by the CPU through the heat sink, so as to keep the temperature of the CPU at a level that can work stably and prevent the CPU from being damaged due to poor heat dissipation. Extend the life of electrical devices.

With the update and iteration of artificial intelligence products, heat-dissipating thermal grease is widely used in new energy, military, medical, aviation, shipbuilding, electronics, automobiles, instruments, power supplies, high-speed rail and other intelligent manufacturing industries; Fat brand manufacturers have sprung up like bamboo shoots after a spring rain, and they have poured into this industry; in the face of so many brand manufacturers, how do we choose?

Which brand of thermal grease is good?

It doesn’t matter what brand of thermal grease you choose, what matters is that the quality is guaranteed. When you are not sure about a brand product, you can buy a small amount for a small-scale test, so as to know whether the quality is good or not and whether it can meet the product performance requirements. Under normal circumstances, the products of the brand have quality assurance, but it is still recommended to choose affordable products with guaranteed quality and a wide range of uses.

What is the thermal conductivity of thermal grease?

There is a gap in thermal conductivity between high thermal conductivity thermal grease and low thermal conductivity thermal grease, and the gap is still very large. According to the data of CoolThermo experimental test, the largest gap between them is 15℃, and the smallest gap is also 11%. ℃; in the same thermal grease with high thermal conductivity, the higher the thermal conductivity, the better the thermal conductivity. So for ordinary users, is it necessary to choose thermal grease with high thermal conductivity?

CoolThermo heat dissipation thermal grease manufacturers think that it is not necessarily. If you only use the computer to do office work and watch TV shows, then ordinary thermal grease is not a problem. Generally, the thermal grease that comes with the radiator is enough. For users with overclocking needs or high-end platforms, it is very necessary to choose a thermal grease with high thermal conductivity, and the higher the better (without considering the price).

On the whole, there is also a gap between thermal grease with high thermal conductivity, but the gap is relatively small. For users with affluent economy, it is not wrong to buy thermal grease with high thermal conductivity directly.

How to buy high-quality thermal grease?

  1. Observe the thermal conductivity. The thermal conductivity of the thermal grease is very important. If the thermal conductivity is too low or too high, the thermal conductivity of the thermal grease cannot be exerted normally. When purchasing, you need to choose according to the product. If you don’t understand, you can consult a professional.
  2. Insulation is very important. Thermal grease is a material used in electrical appliances, and it is in the state of paste. At this time, it must have insulating properties, which can ensure that electrical appliances are safer to use.
  3. The temperature resistance cannot be ignored. When purchasing thermal grease for a product, you must first understand where the product is used. If it is used in harsh environments or environments with temperature requirements, you need to buy thermal grease with strong temperature resistance.

When purchasing thermal grease, you need to pay attention to the above items. However, because the current demand for heat dissipation silicone grease is very large, there are various brands or various prices. Users need to pay attention when purchasing, that is, whether the metal materials will corrode for a long time. If this requirement cannot be met , then no matter how cheap the price and the best thermal conductivity, the thermal grease cannot be used.

What kinds of thermal conductive silicone are there? What are the characteristics? What does it do?

Recently, some customers have inquired about what kinds of thermal conductive silicone are there? What are the characteristics? What does it do? CoolThermo will share with you.

The main function of thermally conductive silicone is to apply it to heat-generating components to conduct heat and dissipate heat. The performance of ordinary thermally conductive silicone depends on the aluminum hydroxide component incorporated into it. Of course, special thermally conductive silicone grease will incorporate an appropriate amount of precious metal oxides. It is mainly composed of four components: polydimethylsiloxane, aluminum hydroxide, quartz powder, methyltrimethoxysilane, and chelated titanium.

Thermal silica gel can be divided into three states: grease, patch and paste according to the different occasions.

Grease-like: such as thermal grease

Thermal grease is paste-like, sticky (here refers to adhesion), non-drying, and can be used for more than five years under normal circumstances. Thermal grease is mainly used to fill the gap between the CPU and the heat sink. This material is also called thermal interface material. Its function is to conduct the heat emitted by the CPU to the heat sink, keep the temperature of the CPU at a level that can work stably, prevent the CPU from being damaged due to poor heat dissipation, and prolong its service life. Because the heat sink and the thermal conduction device are used in the application, even two planes with very smooth surfaces will have gaps when they are in contact with each other. The air in these gaps is a poor medium for heat conduction, which will hinder the conduction of heat to the heat sink. Thermal grease is a material that can fill these voids, making heat conduction smoother and faster.

SMD shape: such as thermal conductive silicone gasket

When used in industry for large-area heat dissipation such as power supplies, thermal conductive silicone gaskets are required because the cost of thermal conductive silicone gaskets is low, non-drying, easy to replace, and has excellent thermal conductivity. High temperature can reach 300 ℃ , the low temperature is generally -60 ℃. In electronic products, it is generally used on the surface of some electronic parts and chips that generate less heat but is not easy to dissipate heat. It is suitable for simple processing of ordinary devices. On the side of a better battery, a thermally conductive silicone gasket is usually attached. , while conducting heat, it can fill the gap between the battery and the casing, and play a buffering and stable role.

Paste: such as one-component adhesive sealant

One-component adhesive sealant is a thermal interface material. One-component adhesive sealant is a thermally conductive RTV adhesive, a colloid that can be cured at room temperature. The color is white or black or transparent. It needs to react with water vapor in the air. It can only be cured. The biggest difference between one-component adhesive sealant and thermal grease is that one-component adhesive sealant can be cured. After curing, it has certain elasticity, adhesion and extensibility. One-component adhesive sealant has Fixing and bonding properties, so in line with general process sealing. The thermal conductivity of the one-component adhesive sealant is the lowest among the three types of silica gels. It is suitable for the thermal conductivity of components such as capacitors and resistors and the bonding between some heating components. The working temperature of the adhesive sealant is generally not more than 200 ℃.

The above is an introduction of CoolThermo to the types, characteristics and functions of thermally conductive silicone. For more information about thermally conductive silicone, visit www.coolthermo.com.

Where to buy thermal grease thermal paste generally in Shenzhen ?

Many cities have very representative industries, which are relatively concentrated. Usually, many manufacturers come to consult, all from the same city. For example, the question of where to buy thermal grease and thermal paste in Shenzhen is usually asked by LED lighting manufacturers located in Shenzhen. Many customers in Shenzhen do not know where to buy thermal grease and thermal grease and how to buy a good one. CoolThermo thermal silica is here to tell you that there are the following channels.

  1. Search for “thermal grease and thermal grease” on the search engine. Through consultation and comparison, you can also directly enter the CoolThermo thermal conductive silicone website.
  2. 1688, Taobao, and other b2b e-commerce platforms, there are many brands of thermal grease and heat-dissipating paste. The prices are good in all aspects, but there are also some black-hearted enterprises, so pay attention to distinguish them when purchasing.
  1. Where to buy thermal grease thermal paste in Shenzhen? Not only online, but also offline. CoolThermo thermal conductive silicone grease manufacturer is also located in Longhua, Shenzhen, you can directly contact the CoolThermo thermal conductive silicone sales staff for offline purchases.

Shenzhen thermal grease thermal paste generally where to buy? It can be found on the Internet. For example, some b2b platforms also have companies publishing information on them. CoolThermo thermal grease manufacturers focus on the production of thermal grease, high thermal grease, CPU thermal grease, high temperature thermal grease, thermal grease and other thermal conductive materials. Three major free services are provided: free consultation, free samples, and free solutions; three major paid services: silicone grease customization services, silicone grease deployment services, and silicone grease analysis services.

What is thermal paste? Introduction to the classification, characteristics and application fields of thermal paste

What is thermal paste?

Thermally conductive cement, commonly known as thermally conductive gel or thermally conductive mud, is a gel-like thermally conductive material made of silica gel composite thermally conductive fillers after stirring, mixing and packaging. This material has some advantages of thermal pad and thermal grease at the same time, and better makes up for the weaknesses of both.

Thermally conductive cement inherits the advantages of good affinity, weather resistance, high and low temperature resistance, and good insulation of silicone materials. At the same time, it has strong plasticity and can meet the filling of uneven interfaces, and can meet the heat transfer requirements in various applications.

Introduction to the classification of thermal paste

Thermally conductive cement can be divided into two products in the industry: one is thermally conductive cement; the other is thermally conductive cement gasket, also known as thermally conductive gel gasket or thermally conductive cement gasket. There is a big difference in method.

Thermal paste is divided into one-component thermal paste and two-component thermal paste. One-component thermal conductive cement is a high-performance thermal conductive gel. It is made of silica gel and filled with a variety of high-performance ceramic powders. The thermal conductive gel has high thermal conductivity, low thermal resistance, and is suitable for heat dissipation Good insulation, can automatically fill the gap, maximize the limited contact area, and can be infinitely compressed.

Two-component thermal conductive cement is a filling material that can be filled in the thermal gap in liquid form. After mixing the two liquids in a 1:1 ratio, they can react at room temperature (or accelerate the reaction by heating), and become an ultra-soft thermal conductive filling material. The reaction process of the two-component thermal conductive cement No by-products, it can be deep-cured, and the cured product has high compressibility and cushioning properties.

The thermally conductive glue gasket is a highly integrated ultra-soft thermally conductive silicone sheet. The thermally conductive glued gasket product preserves the high-quality thermal conductivity of the thermally conductive silicone sheet material, and is easy to adapt to and adhere to parts with uneven surfaces to achieve reliable and complete performance. physical contact.

Introduction to the characteristics of thermal paste

Performance characteristics

Compared with the thermal pad, the thermal paste is softer and has better surface affinity. It can be compressed to a very low thickness, which can significantly improve the heat transfer efficiency. The minimum can be compressed to 0.1mm, and the thermal resistance at this time can be 0.08 ℃·in2/W – 0.3 ℃·in2/W, can reach the performance of some silicone grease.

In addition, the thermal conductive cement has almost no hardness, and will not cause internal stress to the equipment after use.

Compared with thermal grease, thermal paste is easier to operate. 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 fluidity, it is generally not used for occasions with a thickness of more than 0.2mm.

The thermally conductive paste can be arbitrarily formed into the desired shape, which can ensure good contact for uneven PCB boards and irregular devices (such as batteries, component corners, etc.).

Thermal paste has a certain adhesion, and there is no problem of oil out and drying out, and it has certain advantages in reliability.

Advantages of continuous operation

The thermal conductive cement can be directly weighed and used. The commonly used continuous use method is the glue dispenser, which can realize fixed-point quantitative control, save labor and improve production efficiency.

Introduction to the application fields of thermal paste

Thermal paste is widely used in LED chips, drones, communication equipment, mobile phone CPUs, memory modules, IGBTs and other power modules, and power semiconductors.

The application of thermal conductive cement in driving power supply in LED bulb lamp. In the export of LED lamps, in order to pass the UL certification, manufacturers mostly use two-component potting glue for potting. Lamps exported to the United States all require a 50,000-hour warranty. At present, the quality of the LED lamp beads is no problem. The main fault is the power supply. The power supply after potting with potting glue cannot be disassembled. Lamps are scrapped and replaced. If the power supply is partially filled with thermally conductive cement, the heat can be effectively dissipated. If there is a problem with the power supply, the power supply can be easily replaced, which saves costs for the enterprise. Of course, for lamps that require waterproofing, because the thermally conductive cement cannot fill all the gaps and gaps like potting glue, and cannot be waterproof and moisture-proof, potting glue is still required.

Another typical application is in the LED fluorescent tube. For the design of the power supply at both ends, in order not to occupy too much the size of the tube, the space for the power supply at both ends is relatively small, and the power of the 1.2-meter LED fluorescent lamp is usually designed to 18w. To 20w, the calorific value of the driving power becomes relatively large. The thermal paste can be filled into the gap of the power supply, especially attached to the power device to help dissipate heat and prolong the life of the lamp. For some sealed module power supplies, it can be partially filled with thermal paste to achieve thermal conductivity.

Then there is the heat dissipation of the chip. Everyone should be familiar with this method. The silicone grease layer between the similar processor and the heat sink is a principle. Its function is to allow the heat emitted by the processor to be transmitted faster. to the radiator to dissipate.

Similarly, thermal paste can also be applied to mobile phone processors. On the processors of Huawei mobile phones, thermal paste heat dissipation glue similar to silicone grease is used, which has better contact effect than the graphite heat dissipation film only, and the heat conduction is better. will be faster.

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