三維(3D)列印成型技術近年來蓬勃發展，其快速成型與可高度客製化的特性，突破了傳統立體模型的製作過程限制，也減少在製作材料上與成本上的浪費。3D列印又稱為積層製造，是現今市面上常見的快速製造技術[1]。3D列印以數位電子圖檔為基礎，透過電腦及溫度控制的方式，逐層堆疊熔融狀態的原料來構築任意模型的三維物體。3D列印技術應用廣泛，從客製化創意物品到航太與車用零件，甚至醫療領域皆有發展空間[2]。而根據所選的材料性質，可分為低溫及高溫3D列印。
高溫3D列印以金屬粉末為主，如:鐵基粉末 (Fe-based powder)、鋁基粉末 (Al-based powder)以及鈦基粉末 (Ti-based powder)，主要的技術有選擇性雷射燒結 (Selective Laser Sintering, SLS)、選擇性雷射熔化 (Selective Laser Melting, SLM)[3]。磁性材料是由鐵、鈷、鎳及其合金所組成[4]，根據去磁後的剩磁以及矯頑力大小分為軟磁材料以及硬磁材料。軟磁材料的剩磁和矯頑力均很小，特點為容易磁化及去磁，與硬磁材料相比有較高的導磁率和磁感應強度。根據功率、頻率的不同及材料磁特性可分為鐵矽合金 (Fe-Si alloy)、鐵鎳合金 (Fe-Ni alloy)、軟磁鐵氧體 (Ferrite)……等。硬磁材料的特性為磁化後不易退磁而能長期保留磁性，又稱為永磁材料。根據化合物的不同可分為稀土永磁材料、金屬永磁材料、鐵氧體永磁材料。稀土永磁材料是當前所有硬磁材料中最大磁能積(BHmax)最高的。
在我們的研究中，我們利用SLM工藝來列印鐵基軟磁粉末之研究3D列印技術可以透過堆疊熔融材料形成任何復雜的3D元件。 作為高溫3D列印技術之一的選擇性激光熔化 (SLM)的技術將導入在本實驗中，製作出具有軟磁複合 (SMC)結構的馬達元件。由於在製作過程已形成適當厚度的粉末氧化物層，因此產生了具有比傳統矽鋼板更好性能的有競爭力的SMC結構。

Over the past few years, 3D technology were considerably developed in property of rapid prototyping and personalization leaded to breaking through limit of traditional stereo model process and reduced cost and material.
3D printing technology, also known as Additive Manufacturing(AM), is now a common Rapid Prototyping(RP) technology in modern society [1]. Based on CAD files, 3D printing is able to form three-dimensional objects into any shape and geometry by stacking successive layers of melting materials under computer and temperature control. There are wide range applications of 3D printing technology, including producing customized creative items, aerospace and vehicle components, it also can be applied in medical field [2].
Metallic powder materials, such as Fe-based powder, Al-based powder and Ti-based powder, are mainly applied in high-temperature 3D printing. The techniques including Selective Laser Sintering(SLS), Selective Laser Melting(SLM) [3].
Magnetic materials are composed of iron, cobalt, nickel and its alloys[4]. It is divided into soft magnetic materials and hard magnetic materials due to its remanence and coercivity.
Soft magnetic materials have both low remanence and coercivity but are easy to be magnetized and demagnetized. These materials also have higher permeability and magnetic induction compared to hard ones. According to different applications of power, frequencies and magnetic properties, it can be classified as Fe-based alloys, Ferrites and amorphous-based alloys.
Hard magnetic materials, also called permanent magnetic materials. These materials are not easy to be demagnetized but able to retain magnetic force for a long time. Based on different compounds, it can be divided into rare earth permanent magnet materials, metal permanent magnet materials and ferrite permanent magnetic materials. Among them, rare earth permanent magnet materials have the highest maximum magnetic energy product (BHmax).
In our research, we print Fe-based soft magnetic powder by SLM process, Three-dimensional (3D) printing technology could form any complex 3D object by stacking the melted materials. The process of the selective laser melting (SLM), one of the high-temperature 3D printing techniques, was introduced to manufacture the motor component with the soft magnetic composite (SMC) structure in the experiment. Since a proper thickness of the oxide layer of the powder had been formed, a competitive SMC structure which had a better performance than traditional silicon steel sheet was created.

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