Implementering av polymert material : Utredning av möjligheterna i implementering av polymert material i LED-armatur för utomhusmiljö

Sammanfattning: Replacing metals with polymers is getting more and more popular. The main reason for this is that in a lot of cases the same requirement can still be achieved while at the same time using the benefits that polymer brings with them. In some cases the polymers can actually be the favorable choice of material. Fagerhults Belysning AB is one of the companies that traditionally have been using metals but their interest in polymers has grown. The purpose has therefore been to investigate the possibilities of implementing a polymer based material in a LED-armature which will be stationed outdoors and how this realizable potential CADconstruction in a polymer material can be measured against current requirements. The difficulty with this and the main reason why this haven’t been done yet is the general bad thermal conductivity that polymers have. The heat that is being created by the LED-lights has to be taken care of otherwise they will become too warm and will not be able to operate under the same conditions anymore. The side effects will be reduced lifetime and effect. However, if this is taken care of in a proper way and the LED-lights can operate under given temperatures the benefits of polymers can be applied. Two different requirement specifications were created to choose the right materials. The first requirement specifications takes care of the part of the armature where heat is being conducted and needs to be taken care of while the other requirement specifications takes care of the composition and exterior of the armature. Different types of polymers where then selected for the two requirement specification using material database and consultation from plastic suppliers. Another aspect that was part in taking care of the conductive heat two concepts was created. Both of these concepts where then put in a heat simulation program with the polymer that was considered having the highest thermal conductivity. The material that was used for the exterior design was a normal engineering polymer with a low thermal conductivity. However, after the heat simulations the result showed that a polymer with a high thermal conductivity was needed to be used even for the exterior design. Otherwise the heat would have exceeded the limit that was set for the LED-lights. Furthermore, the thermal conductive polymer was considered to be good enough to be used even for the exterior design. Thereby a couple of concepts where created for the exterior design and how it should be composed by using brainstorming, morphology and Pugh’s matrix and a final concept could then be presented. The purpose was thereby fulfilled since the possibilities of implementing a polymer based material had been done together with a realizable CAD-concept. The final result became that the heat that was being generated by the LED-lights can be managed of already existing polymers and at the same time using the benefits with polymers by integrating functions and lower the weight. The usage of a thermal conductive polymer in both the whole armature will lead to high cost for the material. High water- and dust requirements were put on the armature which led to implications in integrating more functions.