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The Universal Selection Source:
Polymer Additives

Boron nitride is an excellent heat conductor and electrical insulator with overall cost reduction while improving physical properties at lower loading.

An alternative to over-engineered metal-based systems for thermal management applications

Metal based Themal management For applications in high heat environments, metal-based systems have historically been the solution of choice. Aluminum, copper or other metals often have been selected for thermal management solutions.

Metal-based thermal management options are still used today; however, these systems are increasingly being replaced by alternative solutions due to price increases in metal and ber requirements for weight savings.

Costly metal-based systems may perform well in terms of thermal management but can show limitations in weight savings and complexity (additional assembly steps or extra parts are needed). Weight and complexity are especially important in electronics, automotive and medical device applications where miniaturization and efficiency needs drive new requirements for thermal management solutions.

An appropriate thermal management system using TCP containing boron nitride (BN) can create a significant market differentiation for designers by optimizing overall system design, functionality and cost.

Design freedom offered by TCPs can yield weight savings and system cost reduction vs. metal

Users are discovering that, in spite of large differences in thermal conductivity between metal and plastics, plastics can offer suitable performance for many thermal management applications.

TCPs containing BN may enable specifiers to reduce overall system cost and meet demands for weight savings. TCPs with BN can offer the opportunity to differentiate through:
  • Good thermal management performance (see LED bulb example below)
  • Design freedom to meet requirements for compact and complex designs (part rationalization and feature integration)
  • Color freedom (easy to color white compound) and good aesthetics (soft touch)
  • Higher durability vs. metal (no corrosion)
  • Weight savings opportunities

Good thermal management performance with electrical insulation

BN is a unique ceramic material that can improve thermal conductivity while remaining electrically insulating. It is, therefore, an attractive alternative to metal, which often requires additional parts or treatment to obtain electrical insulation properties.

The housing of an LED bulb is an example of an application where BN-filled TCPs have successfully replaced metals. In a number of applications, LED bulbs operate in convection-limited environments, which means the bottleneck in the heat dissipation pathway is the heat transfer from the heat sink to the ambient air. Theoretical modeling of heat transfer from a heat sink in convection-limited environments indicates that thermally conductive plastics can replace aluminum as the heat sink material. And with minor design changes, plastics can sometimes offer even more effective heat transfer.

Good thermal management performance with electrical insulation


Lower Cost & Similar Thermal Management Performance to Metal: TCP containing BN

The plot below shows the results from theoretical modeling of a simple heat sink made of either aluminum (6 fins x 5 mm thick x 25 mm long) or a 5 W/mK plastic (7 fins x 4 mm thick x 25 mm long). The temperature of the heat source was set so that both heat sinks dissipated 3 W. A total heat dissipation of ~3 W is typical of what might be expected for a 60 W-equivalent LED bulb. As shown below, the model indicates that the operating temperature of the plastic heat sink could be about 2°C lower than the aluminum heat sink at the heat source with a very minor design modification. Had the same design been used, the plastic could have been only 3°C higher than the aluminum.

Results from theoretical modeling of a simple heat sink


TCP containing BN The use of BN-loaded thermally conductive plastics for effective thermal management of an LED bulb was validated by success in a commercial application. The IR image on the right shows the steady state operation of a 10.4 W LED bulb (equivalent to a 60 W incandescent bulb) that used a BN-loaded plastic heat sink. The temperature of the hottest spot on the heat sink sink was 68°C, very much in line with what would be expected from an aluminum heat sink. Note: Test data. Actual results may vary.

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