The Investigation Of High Power LED Multiple Thermal Functional Interface Materials

With the development of human lighting technology & the improvement of the consciousness of human being to environment, more and more new technology and new invention what are as the sign of high-efficiency,saving-energy,environment-protection,long-life appeared in lighting field ,then gradually apply much.One of these signs is what has the characteristic of high luminaire,high light-efficiency,cold light-ray,tiny volume,quick reaction,high power efficiency,full color light,high displaying true color,solid light source,long-life etc,belongs to high power light emitting diode (HPLED in brief named).By the application of HPLED expands from decorative lighting to general lighting ,as the result new requirements are naturally born, the first requirement is that light luminance per power continuous improves higher,the second requirement is by gathering power in certain area to reach the goal of improving total light luminance .for example HPLED encapsulation volume per unit does not changes but its power improves from 1W, 3W to 5W.which has located in experimental grade will has more high power. All of above requiring how to conduct thermal from HPLED light emitter core to lightshell or its thermal conductivity instrument in prestissimo and low thermal resistance ways,avoiding the fatal effection of thermal deposition resulting in temperature increasing brings to HPLED light emitter core.The classic application equipment of HPLED is HPLED lamp. The tiny or small is its outstanding merit that differs from traditional lighting.Therefore the thermal conductivity equipment of HPLED are always in passive methods such as: thermal conductivity, natural thermal convection,thermal radiation.The two forward methods are primary.From HPLED light emitter core to lightshell or its thermal conductor equipment unavoidable through one or two or three solid interface. At present according to the true application ,much more two solid interfaces are common,then how to reduce these solid interfaces thermal resistance lowestly,so thermal current may pass through that in utmost degree will be the best way to avoid the PN junction temperature of HPLED light emitter core reach too high.The research object in this article is a certain functional multiple thermal interface material what has characteristic of phase-change : solid-liquid phase-change can connect between solid interface surface with no gap.Which also includes organic silicone element etc, which insures no chromatography ,no local-gathering,non-lost,etc.Moreover silicone has the characteristic of relative high thermal conductivity factor,weak electric conductivity,low cost so that very exactly fits to the application of HPLED solid interface.According to the thermal conductivity characteristic of phase-change functional multiple materials we have adopt limited particle therory analysis in this article ,by special computer thermal anaylsis technology,aim at certain HPLED flood lighting model,established computer model .and combined a series of non-metal thermal interface materials experiments,which established in certain power,different thickness,different temperature,different trasaction,different composition, to acknowledge thermal conductivity effection of the material to HPLED flood lighting by its ascend and descend temperature curve,and certain measuring spots temperature changing,conclude what should be refer in HPLED lighting application...