Light emitting diodes (LEDs) are extremely efficient in mitigating heat during operation. However, with manufacturers pushing the limits of LEDs, traditional methods for heat dissipation may not be enough to keep the fixtures going, especially for businesses with complex lighting requirements.
Advantages in Heat Dissipation
Thermal management has always been the focus of many leading LED manufacturers. Heat generated from the lights must be dissipated properly in order to ensure the fixtures are working to their full potential. Traditionally, aluminum heat sinks were used to move heat away from the unit. But now, more and more designers are opting to use thermally conductive plastics due to their robust features. Units that are unable to effectively move heat away from the fixture suffer from color shifts, decays in brightness and failure. In LED applications, thermal conductive plastics may be applied on the lamp holder and heat sink. It is not ideal for packaging material, due to high reflectivity and retention of reflectivity requirements. When used as a plastic heat sink, it offers excellent heat dissipation.
On the other hand, UL listed units for wet locations refer to a location where water or liquids may drip, splash or flow on the electrical parts of a fixture. Exterior walls, garden landscapes, open-air decks and roofs are examples of wet locations in outdoor settings. Damp and wet UL ratings are the most common types of protection that individuals look for when selecting RGB outdoor lights. When it comes to the type of lighting technology, LEDs perform exceptionally well in outdoor locations (due to their solid state design), compared to traditional options, such as incandescent and fluorescent lamps.
An example of a sector that is pushing the boundaries of thermal conductive plastics in LEDs is the automobile industry. In a case study by PolyOne Therma-Tech, researchers created a solution for a car manufacturing business that wanted to avoid the use of aluminum in lights, due to added weight, high production costs and negative impacts on fuel consumption. Scientists pursued the application of thermal conductive plastic to decrease heat build-up and prevent light degradation. Switching to the new material allowed the company to rely on its current injection-mold machines, avoiding the need to purchase $11,500 of new equipment. Furthermore, the business is currently saving $14,400 per year just by replacing the aluminum parts.
Outside of the automobile space, the flexible material can be applied in the following sectors: electronics (chipsets and IC assembly), industrial (coils, pumps and transformers), heating/cooling (HVAC and radiant heating), and medical (devices and instrument casings). For businesses that are concerned about pollution and energy consumption, thermal conductive plastics provide a reclaim rate of up to 30 percent, and may help lower material wastage through molding.
Benefits in LED Manufacturing
The use of thermally conductive polycarbonate is beneficial for LED manufacturers. Such materials can reduce assembly steps during production. It also has the potential to reduce cost per unit in compact applications. After demolding, after-treatment is not required, compared to aluminum-based pieces. This greatly decreases the time spent on the production line, and wastage is minimized when shaping the piece for specific light models.
Traditional plastics are known for their insulating properties and prevent heat from actively escaping the fixture. Because of this, specially manufactured conductive plastics with robust fillers had to be created to meet the needs of high intensity LEDs, allowing the units to distribute heat evenly and away from the heat source.
To promote electrical conduction properties, manufacturers may add graphite or carbon fibers, or a combination of plastic and metal (hybrids). When boosting electrically insulating features of thermally conductive plastics, manufacturers may introduce ceramic or mineral fillers to the polymer solution. The modified material has the potential to reach up to 10 W/mK of thermal conductivity.