Thermally conductive polyamide replaces aluminum in LED heat sinks

  • Weight reduction of around 50% enables use of spring fixations in the ceiling
  • High thermal conductivity (up to 14 W/mK)
  • Good flow properties, easy to mould

Market leader Osram is using Stanyl TC thermally conductive polyamide 46 of Royal DSM in the heat sinks of their new large LED downlights. Chosen ahead of aluminum, the material can be easily injection moulded into complicated geometries that effectively remove heat from around the LED light source, thus ensuring a long lifetime.

LEDs are taking over from incandescent and fluorescent lighting

Osram is one of the world’s leading lighting companies. The L and XL versions of its LEDVANCE series are the first LED downlights (lights that are built into the ceilings of shops, offices, and domestic accommodation) from the company with a heat sink in plastic rather than in aluminum.

LEDs are quickly taking over from incandescent and even fluorescent lighting in buildings, due to numerous advantages: very low energy consumption, potential lifetimes as much as 50 times longer than traditional bulbs, higher efficiency and reduced environmental impact.

Osram LED downlights

Osram LED downlights keep cool with thermally conductive Stanyl TC polyamide 46 from DSM (source: DSM Engineering Plastics: DSMPR435)

Thermal management as a challenge

A key challenge that lighting manufacturers need to overcome with LEDs is thermal management: the heat generated by the LED has to be dissipated in order to ensure that their potential to provide high quality light over many years is fully realized. Aluminum heat sinks are widely used to pull the heat away from the LED, but designers are increasingly calling for alternative materials that can provide them greater design freedom and lower weight.

Good flow properties – easy to mould

DSM’s Stanyl TC was developed specifically for this application. It has sufficient thermal conductivity (up to 14 W/mK) to dissipate the heat generated by the LED. It also features the good flow properties common to all polyamides that enable it to be moulded into complicated shapes with high surface-to-volume ratios that enhance heat dispersion. The high thermal conductivity of Stanyl TC also translates into short production cycle times, and once demoulded, no after-treatment is needed, unlike solutions in aluminum.

Weight reduction of around 50% enables use of spring fixations in the ceiling

Stanyl TC is characterized by high mechanical properties (strength, stiffness, impact resistance) that are retained under cyclic thermal loads experienced in use. By selecting this material grade, Osram was able to reduce the weight of the housing by around 50 % compared to aluminum. This facilitates the installation of the luminaire and enables the use of spring fixations in the ceiling. The material complies with flammability requirements according to IEC and UL safety standards.


Related Articles & Comments

Comments are closed.