製備氮化硼填充複合材料及其特性研究

Study on Properties of the Boron Nitride Composite Fillers

林敬堯(Ching-Yao Lin)

指導教授 ： 蘇程裕

國立臺北科技大學/機電學院/製造科技研究所/碩士(2011年)

摘要

傳統的散熱元件需最佳化設計，以得到最佳的散熱效能，各種新的散熱元件及材料技術也開始應用於LED散熱，絕緣基板是目前高功率LED產品相當重要的組件，而絕緣散熱基板最大的熱瓶頸即是介於金屬基板與銅箔電路之間的高分子基導熱絕緣材料，因其熱傳導率只有0.23W/m•K左右，是基板熱阻的主要來源。
本研究係成功使用噴霧造粒法製備氮化硼/高嶺土、氮化硼/釉料以及氮化硼/SMPL-X複合球體做為高分子聚合物之填充材料，研究成果顯示，球型複合粉體添加於環氧樹脂中其複合粉體之表面形貌對於粉膠混合後之黏度有絕對性的影響，表面愈緻密之球型粉體與環氧樹脂間的潤濕較好進而降低粉膠混合後之黏度。複合粉體之強度取決於助燒結材料粒徑分佈與易燒結性而定，粒徑分佈越窄與越易燒結之助燒結材料對於複合粉體之強度有正面幫助。由結果得知，經球型化表面緻密的高強度XB19複合粉體可以有效的提高環氧樹脂複合材料中無機材料的添加比例，並大幅改善六方氮化硼只能沿單一方向進行熱傳導的缺點，使熱傳方向成多向性增加整體熱傳效率。並且經球型化之氮化硼複合粉體其輻射吸收強度高於純片狀氮化硼，對於熱輻射而言提高吸收率相對增加放射率，使熱輻射散熱效率大幅提升。

關鍵字

散熱絕緣層 ； 陶瓷複合粉體 ； 氮化硼 ； 高嶺土 ； 釉料 ； 複合材料

並列摘要

The highest efficiency of heat-dispersion has been induced by optimizing the experimental design on heat-dispersive devices. At the same time, there are many outstanding designs of heat-dispersive devices and innovative techniques used in LED (Light Emitting Diode) application. Presently, insulator has emerged as a primary device for LED. On the other hand, the thermal resistivity of insulator has been attracting considerable attention as a key point due to its’ lower thermal conductivity of about 0.23 W/m•K between the metal substrate and circuit.
In this study, these composite powders such as h-BN/ Kaolin, h-BN/Glazes and h-BN/SMPL-X were synthesized as the filler polymer using spray dry technique. The results indicate that during the process of mixing spherical composite powder into Epoxy, the effect of spherical composite powders’ morphology on the viscosity of mixed colloid is significant. That means a decrease in the viscosity of the mixed colloid apparently depends on the wettability of spherical composite powder. In the meanwhile, the strength of composite powders strongly rely on the particle size and sintering ability. The content of inorganic material added to epoxy is effectively enhanced using high strength, densely packed surface and spherical XB19 composite powder. Besides, the spherical XB19 composite powders increase the thermal conductivity of hexagonal BN, which can facilitate the highest thermal-dispersive efficiency because the thermal-radiation absorption of spherical BN is much higher than platelet BN.

並列關鍵字

Insulation ； Ceramic composite powder ； Boron Nitride ； Kaolin ； Glaze ； Composite materials

參考文獻

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