LED 히트싱크용 금속 발포체 개발 및 특성분석

Abstract

LED is attracting the interest due to its important impacts on illumination industry. However, currently, the thermal problem that is brought by heat generated within the LED itself is still a barrier that limits the stability, reliability and lifetime of LED. Therefore, effective heat dissipation of LED packages with low thermal resistance are significant to improve the performance of LED. The previous method of manufacturing the Aluminium heatsink needs high temperature. This generally leads to growth of manufacturing cost. It is possible to make the heatsink without high temperature for the melting process of previous method. In this study, first of all, the metal foam heatsinks were fabricated by using various metal powders and binders. The component of metal foam were investigated by using the energy dispersive X-ray spectroscopy(EDS). The microstructure was examined through field-emission scanning electron microscopy. The compressive strength was measured by universal testing machine. The Strength of Zn based matal foam was about 4.14 MPa, whice was the highest among various metal foam. BET surface area of Zn based metal foam was about 9.467 m2/g, which was much higher in comparison with other metal foams. Finally, the performance of heat dissipation were measured by using a thermal imaging camera. The metal foam heatsinks and the commercial aluminium heatsink were combined with each LED lighting fixture. We measured the actual heat dissipation effect of heatsink, the temperature of LEDs combined with Zn based metal foam and Al based metal foam is about 48.6 and 48.2 ℃, which showed an efficient heat dissipation by 95% compared with commercial LED heatsink. These metal foams are expected to fine potential application such as heatsink of LEDs and other electronic devices.