Introduction
In a way, LED lights are convenient because they don’t give out heat in the form of infrared radiation. Hence they can stand in areas where infrared radiation will cause damage.
But one area to be aware of is that LEDs produce innermost heat, and this unwanted heat must be tackled. This brings about the LED heat sink.
LED heat sinks are virtually must-have equipment for the manufacturing industry of LED lights to help curb the equipment’s heat.
In this article, we provide extensive knowledge about LED lights and their heat sinks, how they are produced and how you can get the best out of them for maximum satisfaction.
Read through for everything about LED heat sinks.
What Is a LED Heat Sink?
The equipment responsible for absorbing the internal heat generated by a LED light and dispersing the absorbed heat into the atmosphere is a LED heat sink.
The LED heat sink focuses on cooling or maintaining the temperature of a LED light which is an essential criterion for the operation and lifespan of a LED light. This, in turn, makes LED heat sinks very important.
There are different stages of producing the LED heat sink with other materials(discussed in detail below).
Why Do LED Lights Need a Heat Sink?
The inefficiency of the semiconductors in the LED light for generating energy causes about 70% to 95% of the power input to be lost in heat. With all these inevitable heat generating, it is crucial to reduce or evacuate it to reduce the internal temperature of the LED light.
As mentioned earlier, a constant high temperature in the LED can cause damage due to the increase in the internal temperature. If the junction temperature is increased, the brightness of the bulb is reduced, and the lifetime is shortened. When a LED is overheated, it may not fail once, but the luminance is lowered. Although sometimes, it may cease to function once.
All these scenarios led to the introduction of the LED heat sink and its significant importance. The heat generated by the LED must be conveyed outside and cooled, and a good LED heat sink does this very well in three different methods
● Radiation
● Conduction, and
● Convection.
How is it made?
The most used methods of creating LED light heat sinks are the forging, die casting, stamping and extrusion metal forming procedures. A lot of other systems are used. They are explained in detail below:
Die Cast
In making LED heat sinks with die-casts, a molten material(aluminum) is filled into a metal cast and held in place with hydraulic pressure. Depending on the shape and size of the mold(which can vary vastly), different LED heat sinks for various applications are made. The result of this method is surfaces textured and rough.
The ideal method for mass production as it is cost-effective and efficient.
Forging
This process involves compressing a metal in a specified mold until it possesses the mold’s shape. Sometimes referred to as cold forging due to the fact it is made at room temperature.
This method creates a heat sink with a very high thermal conduction capability, up to 80% better than the die-cast method. Other advantages of its heat sink are surface quality and mechanical endurance significance.
Extrusion
The extrusion method involves pushing an aluminum material into a hole to shape it. Different sizes of the LED heat sinks are obtained by cutting the shaped part to the required size.
With this method comes better cooling. More than the Forging method. Its thermal conductivity is sublime as no pores form on the part’s surface after production, which can affect it.
Machining
This method is of little use in making LED sinks because of the ineffective consumption of materials associated with the technique. It involves using a gang saw to cut through a metal block.
The production process is low in resistance to heat which causes the part to be highly thermal conduct-able. Also, small batches have a short lead time.
Stamping
In stamping, the metal to be used is placed in a die and labored into different sizes, shapes, and geometries using other metalworking techniques such as pressing, blanking, embossing, flanging, punching, or bending.
It is cost-effective and ideal for the large-scale production of full-sized runs. The typical procedure for inserting fins and making stake fins.
Stripping
This method involves cutting away or skirving a material(or ribbon) continuously. The material is usually placed on a solid ring rotator.
The shape and the thickness of the strip are controlled by applying a tensile force to the emerging chip or ribbon.
Bonding
To produce LED light heat sinks with the bonding method, a bonding agent such as solder is put in place to create heat sinks grooved by an assembly of fins with high density. The fines are plate-like with high density to increase the heat conduction rate.
Bonding methods can be done with a wide range of materials. Die casting, machined, or Extrusion can be used to make the groove bases. Stamping or extrusion can be used for the plate fins.
What Material Can Be Used For LED Heat Sink?
Two materials are mainly used for the heat sink Manufacturing processes which are Copper and Aluminum.
Although the main reason for the heat sink is to conduct heat and copper has a very high thermal conducting rate, aluminum is the preferred choice. This is because even though the aluminum thermal conduction rate is lower, it is moderate. And aluminum has high corrosion resistance, is ideal for mass volume output with standard methods, and is cost-effective.
Also, production using an aluminum can be combined with other materials to facilitate the LED lights heat sink’s effectiveness. Copper material might be added to stimulate the heat sink rate of conduction and strength. Magnesium can be added to increase tensile strength, while silicone can also be added to increase fluidity during production.
Stainless steel is sometimes used for its corrosion-resistant characteristics and aesthetic finish. But they are less thermally conductive compared to copper or aluminum.
Ceramics is one material also used. Coupled with their moderate thermal conduction, they are implemented because they are cheaper and have dielectric constants. However, ceramics tend to break more quickly as they are brittle.
MCPCBs: How It Helps the LED Heat Sink?
The Metal core printed circuit board, also known as MCPCBs or Metal core PCBs, is mainly used in the circuit to move away or dissipate the heat generated from the components.
Usually, LEDs are mounted on PCBs which produce a lot of heat that can cause damage. Hence, the metal core PCB is implemented to curb this problem.
MCPCBs possess an aluminum material at the base. The metal helps to move away the heat generated by the board in the circuit to less vulnerable components, in this case, a heat sink to cool it. MCPCBs are very useful for managing heat in the circuit.
The Metal core PCBs are essential, especially in devices with a considerable generation of heat, as they facilitate the cooling operation because the installed fans are inadequate for sufficient cooling. The Metal core can effectively conduct heat(being a metal) to a cold section.
The parts of the Metal core PCBs are the Dielectric layer, circuit layer, metal core layer, copper layer, and solder mask.
LED Heat Sink Calculator
The standard formula for calculating heat sink is below.
θs = (Tj-Ta) — θjc — θb
Pd
θs = Heat sink thermal resistance
θjc = thermal resistance between LED case and sink( LED COB module’s thermal resistance).
Tj = maximum junction temperature.
Ta = Ambient air temperature around LED heat sink.
Pd = power distributed from the LED module.
The above formula or calculation will provide you with a value to enable you to decide on the proper heat sink.
LED Heatsink Housing
The appropriate housing for the LED lights heat sink provides a channel to assemble various components. It comes in different shapes and sizes according to the LED to fit in well. There is an opening in the base for electrical wire and threads.
How Do You Mount a LED Heatsink?
To mount the heat sink of a LED light, firstly, the pads of the heat sink should be skimmed to mount the LED properly. A solder gauge for thinning is used.
The contacts and pads are appropriately aligned and soldered individually. A multimeter is used to ensure the connection’s effectiveness.
Conclusion
Some LED lights are specially designed to emit infrared radiation. But most are not, and they generate a lot of heat.
It is important to note that to increase the longevity of your LED lights, you must first manage the amount of current flowing to the LED. If you input more current than the average capacity it can take, it will fail at once. Failing to apply a heat sink or the proper heat sink will reduce its brightness and lifespan. All work side-by-side.
If you are looking to balance the effectiveness of your LED lights, you should apply the proper heat sink. At Kenfatech, we are a manufacturing company that has served the international market across the globe for more than two decades.
Our cabinet is full of engineers with the whole experience, producing heat sinks for years.
Contact us now for your LED light heat sink in the fastest time range.
