介金屬化合物具有特殊高溫機械性質、化學及結構穩定性等優點，然而低延展性特性使其應用受到很大侷限。近年來結合高熵合金概念，透過增加元素種類，降低合金系統有序程度方式使變形更加均勻，且缺陷生成不再侷限於表面，轉以晶格扭曲處生成。因此本研究對高熵介金屬化合物NiCoFeTiZrHf (6C) 進行微觀機械行為與缺陷回復分析。本研究先以EBSD、EDS、XRD和TEM進行基本性質分析，再針對 (110) 晶粒進行奈米壓痕測試及臨場壓縮測試，並透過TEM 觀察及臨場加熱了解缺陷回復行為。研究結果顯示6C高熵介金屬化合物主要為 B2 結構所組成 (含有少量 Fe2Zr 相)，針對 (110) 晶粒測試可發現有別於傳統合金之變形行為，由於內部缺陷以大量糾結部分差排為主，使變形呈現桶狀變形的方式。並且於12000 μN 600 s和循環測試皆可發現其微小缺陷在300°C下存在缺陷回復行為，該結果對於未來高熵介金屬化合物研究提供重要訊息。

Intermetallic compounds have the advantages of special high-temperature mechanical properties, chemical and structural stability, etc. However, the application of these alloys still have some limitations because of the low ductility characteristics. In recent years, the concept of high-entropy alloys has been combined with intermetallic compounds. By increasing the types of elements and reducing the degree of order in the alloy system, the deformation is more uniform, and the generation of defects is at the distortion of the crystal lattice instead of the surface. Therefore, this study focuses on the micro-mechanical behavior and defect recovery of the high-entropy intermetallic compound NiCoFeTiZrHf (6C). In this study, EBSD, EDS, XRD and TEM were used to analyze the basic properties, and then nanoindentation test and in-situ compression test were performed on (110) grains, and the defect recovery behavior was understood through TEM observation and in-situ heating. The research results show that the 6C high-entropy intermetallic compound is a mainly composed of B2 phase (with minor Fe2Zr phase) The (110) grain test shows that it is different from the deformation behavior of traditional alloys. Because the internal defects are dominated by a large number of entangled partial dislocations, the deformation shows a barrel-like deformation. In 12000 μN 600 s test and cycle test, it can be found that the small defects have recovery behavior at 300°C. These results provide important information for exploring future research of high-entropy intermetallic compounds.

目錄
誌謝 I
摘要 II
Abstract III
目錄 IV
圖目錄 VIII
表目錄 XV
壹、前言 1
貳、文獻回顧 2
2-1介金屬化合物 2
2-1-1基本性質 2
2-1-2結構與組成 4
2-1-3低延展性 6
2-2形狀記憶合金 8
2-2-1基本特性 8
2-2-2核心效應 10
2-2-3種類及應用 12
2-3高熵合金及其介金屬化合物 14
2-3-1高熵四大核心效應 14
2-3-2 FCC高熵合金 17
2-3-3 BCC高熵合金 19
2-3-4高熵介金屬化合物 21
2-3-5高熵形狀記憶合金 23
2-3-6高熵介金屬化合物特殊機械行為 25
2-4材料機械行為及其影響因素 27
2-4-1晶體結構 27
2-4-2異向性 29
2-4-3組成成分 31
2-4-4尺寸效應 33
2-5變形機制與缺陷 35
2-5-1介金屬化合物 35
2-5-2形狀記憶合金 38
2-5-3金屬玻璃 40
2-6研究目的 42
參、實驗步驟 43
3-1實驗規劃 43
圖3-1 43
3-2實驗流程 44
3-2-1高熵介金屬化合物試片 44
3-2-2 EBSD晶粒方向鑑定 44
3-2-3 EDS成分分析 45
3-2-4 XRD晶體結構分析 45
3-2-5 TEM微結構觀察 45
3-2-6奈米壓痕測試 47
3-2-6聚焦離子束 (FIB) 微米柱試片製備 50
3-2-7臨場SEM微米柱壓縮測試 52
3-2-8微米柱縱剖面TEM分析 54
肆、結果與討論 55
4-1晶粒方向鑑定 55
4-2 EDS成分分析 57
4-3 XRD晶體結構分析 59
4-4 TEM微結構觀察 61
4-5 變溫變應變速率之奈米壓痕測試分析 62
4-5-1彈性模數 (Elastic Modulus) 62
4-5-2奈米硬度 (Nano Hardness) 63
4-5-3位移突進分析 (Burst) 66
4-6 臨場SEM微米柱壓縮測試 69
4-6-1 變溫變應變速率壓縮測試 69
4-6-2 12000 μN持重600 s 77
4-6-3 循環測試 81
4-7縱剖面TEM試片觀察 86
伍、結論 92
陸、參考文獻 94

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