Application of Graphene Inorganic Ink in LED Heat Dissipation

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LED light-emitting device introduction Semiconductor light-emitting diode (LED) is a commonly used light-emitting device, which emits energy through the recombination of electrons and holes, and efficiently converts electrical energy into light energy
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It has a wide range of uses in modern society, such as lighting, flat panel displays, medical devices, etc.
, among which it is the most widely used in the lighting field
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Like traditional light sources, semiconductor light-emitting diodes (LEDs) generate heat during the conversion of electrical energy into light energy, which depends on the overall luminous efficiency
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Under the action of external electric energy, the radiation of electrons and holes recombine to produce electroluminescence.
The light radiated near the PN junction also needs to pass through the semiconductor medium and packaging medium of the chip itself to reach the outside (air)
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Combining current injection efficiency, radioluminescence quantum efficiency, and external light extraction efficiency of the chip, in the end, only about 30-40% of the input electrical energy is converted into light energy, and the remaining 60-70% of the energy is mainly caused by non-radiative recombination of lattice vibration.
The form transforms heat energy
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2.
The influence of LED heat dissipation structure on heat dissipation.
LED lamps made by LED light sources are mainly composed of LEDs, heat dissipation structures, drivers, and lenses
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Generally speaking, whether the LED lamp is stable and the quality is good or bad, and the heat dissipation of the lamp itself is very important.
The heat dissipation of the high-brightness LED lamps on the market often uses natural heat dissipation, but the effect is not ideal.
Therefore, heat dissipation is an important factor.
Partly, if the LED does not dissipate heat well, its lifespan will also be affected
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Structural devices that affect the heat dissipation of LED lamps include sapphire substrate materials, LED chips and heat sinks
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The extremely low thermal conductivity of the sapphire substrate material increases the thermal resistance of the device and produces a serious self-heating effect, which has a devastating effect on the performance and reliability of the device; the heat is concentrated in a small chip, and the chip temperature rises , Causing non-uniform distribution of thermal stress, chip luminous efficiency and phosphor lasing efficiency decrease.
When the temperature exceeds a certain value, the device failure rate increases exponentially
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Statistics show that for every 2°C increase in component temperature, reliability decreases by 10%
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When multiple LEDs are densely arranged to form a white light illumination system, the problem of heat dissipation becomes more serious
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Solving the problem of heat management has become a prerequisite for high-brightness LED applications
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The most direct way to reduce heat dissipation and increase the brightness of power LEDs is to increase the input power.
In order to prevent the saturation of the active layer, the size of the pn junction must be increased accordingly.
Increasing the input power will inevitably increase the junction temperature, and then Reduce quantum efficiency
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The increase in the power of a single tube depends on the ability of the device to extract heat from the pn junction.
While maintaining the existing chip material, structure, packaging process, current density on the chip and equivalent heat dissipation conditions, the size of the chip will be increased separately.
As a result, the junction temperature will continue to rise
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3.
Common radiator heat dissipation methods Generally speaking, according to the way heat is taken away from the radiator, the radiator can be divided into active heat dissipation and passive heat dissipation
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The so-called passive heat dissipation means that the heat of the heat source LED light source is naturally dissipated into the air through the heat sink, and the heat dissipation effect is proportional to the size of the heat sink
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Active heat dissipation is to disperse the heat generated by the LED lighting process through some design outside the system
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Active cooling can be divided into air cooling, liquid cooling, heat pipe cooling, semiconductor cooling, chemical cooling and so on
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Among them, air-cooled heat dissipation is the most common LED heat dissipation method.
The heat sink materials are mainly aluminum and copper materials, which are generally made of fins to increase the heat dissipation area
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This kind of radiator mainly relies on heat conduction and air convection to dissipate heat, and the heat dissipation efficiency is improved by increasing the heat dissipation area and increasing the air flow rate
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However, the extent to which this method improves the heat dissipation effect is limited and will be affected by the ambient temperature and air flow rate
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4.
New type of heat-dissipating paint-Flamingo graphene paint.
As we all know, there are three ways to conduct heat: heat conduction, convection, and radiation
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If the surface of the metal radiator is coated with a layer of radiant paint, the convection and radiation synergy can be realized, which can greatly improve the efficiency of heat dissipation, and it will not be affected by the ambient temperature and air velocity, and it will bring a qualitative leap in performance
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Graphene has excellent electrical and thermal conductivity.
It has the highest heat radiation efficiency among common materials.
It can convert a large amount of heat into far-infrared radiation.
When used in radiators, it can improve thermal conductivity and heat dissipation efficiency.
It is very suitable for heat dissipation coatings
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However, traditional graphene heat-dissipating coatings use organic resins to form films, which are easy to decompose, age, or even burn or burn in high-temperature and high-ultraviolet environments, and organic resins have low thermal conductivity, which greatly reduces the heat dissipation efficiency and service life of graphene coatings
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Flamingo graphene paint uses inorganic high-temperature resistant adhesive as the film-forming material, and uses high-temperature welding to form the film.
It will not decompose, age, or burn in a high-temperature environment.
It has high thermal conductivity, high infrared emissivity, and coating The advantages of good strength, weather resistance and corrosion resistance
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It can be applied to the heat dissipation components of home appliances, HVAC, and industrial equipment, such as air conditioning radiators, home appliances radiators, heating system radiators, LED lamp radiators, heat exchange equipment radiators, etc.
It can cover carbon steel, stainless steel, aluminum, Substrates such as copper have greatly expanded the application range of graphene in the field of heat dissipation
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Customers who are interested in understanding graphene coatings can consult Guangdong Qichen engineers to learn more! Guangdong Qichen New Material Technology Co.
, Ltd.
was established in November 2015 with a registered capital of 10 million yuan.
The company is committed to the technical application of inorganic non-metallic functional powder materials and their in-depth development products! Mainly engaged in the application formula design, process realization, production and sales of inorganic powder materials
.
It has three production bases in Heyuan, Lianping and Meizhou in Guangdong, and 6 deep powder processing production lines.
It is also a large-scale jet mill non-metal powder manufacturer in South China, with an annual output of up to 50,000 tons
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The main products include: sub-titanium powder, anhydrous transparent powder, glass powder, silica powder, low melting point glass powder, special high-temperature coatings and other inorganic powder series products, which have been widely used in: coatings, paints, inks, adhesives , Silicone rubber, plastics, refractory materials, casting, grinding and polishing materials, and hotel entertainment, municipal building materials, agricultural heating, medical equipment, transportation vehicles, industrial equipment, military technology and other industries
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