本研究藉由機械合金製程探討耐火高熵合金的機械性質與顯微結構變化，並藉由添加具有延展性的黏結相來提升耐火合金整體的延展性。第一部分為WVTaTiCr耐火高熵合金在不同元素比例與製程變化的影響。第二部分到第四部是藉由添加黏結相到耐火合金，並探討不同種類的耐火基地相與黏結相的變化，並從中選出較佳的合金設計以WMoVTi為基地相，分別添加CoFeNi或7Ni1.5Co1.5Fe為黏結相做進一步的探討。第五部份是改變黏結相添加在耐火合金中的含量，透過提高黏結相的比例，近一步提升耐火合金在室溫的壓縮延展性。由前幾個部分的結果可得知合金內部會產生大量的氧化鈦，因此在第六部分是藉由添加額外的氧化劑Y元素來抑制合金內氧化鈦產生的數量，使Ti元素可以固溶於基地相而不是向外析出形成氧化物。第七部分則是探討Mo含量的變化對基地相與黏結相的影響。第八部分則是藉由降低Ti的比例來減少氧化鈦的產生，並將減少的比例轉移到V元素上，觀察兩者變化對合金的影響。

In this study, the mechanical properties and microstructure changes of refractory high entropy alloys fabricated by mechanical alloying were investigated. The ductility of refractory high entropy alloys was further improved by adding a ductile binder phase. In the first part, we focused on investigating the influence of the element ratio and processing change on the WVTaTiCr refractory high entropy alloys. The second to the fourth parts are to investigate the effects of different matrix and binder phases on high entropy refractory alloys. In this study, the WMoVTi alloys with the binder of the CoFeNi and 7Ni1.5Co1.5Fe were further investigate. In the fifth part, the content of the binder phase in refractory high entropy alloys was modified. By increasing the proportion of the binder phase, the compressive strain of the refractory alloy at room temperature can be further improved. Based on the results from the previous parts, it was observed that a large amount of titanium oxides was generated in the model alloys. Therefore, in the sixth part, an additional oxidant element, Y, was added to suppress the formation of titanium oxide in the alloys. It can promote the titanium element to dissolve into the matrix phase restricting the formation of precipitates and oxides. The seventh part discussed the influence of the Mo content on both the matrix phase and the binder phase. The eighth part aims to decrease the production of titanium oxide by reducing the proportion of Ti and transferring the reduced proportion to the V element. The objective is to observe the influence of these changes on the refractory high entropy alloys.

第一章 緒論 1
1.1 前言 1
1.2 研究動機 1
第二章 文獻回顧 3
2.1 高熵合金 3
2.1.1 高熵效應 4
2.1.2 晶格應變 4
2.1.3 延遲擴散 4
2.1.4 雞尾酒效應 5
2.2 機械合金(Mechanical Alloying; MA) 6
2.2.1 機械合金原理 6
2.2.2 影響機械合金因素 6
2.3 耐火高熵合金 8
2.4 細晶強化 9
2.5 散佈強化 10
2.6 中熵合金 11
2.7 W-Ni-Fe-Co 11
第三章 研究方法及實驗步驟 13
3.1 合金粉末製備 19
3.2 機械合金球磨 21
3.3 壓錠成型 21
3.4 高真空燒結 22
3.5 顯微結構分析 23
3.5.1 X光繞射分析(X-ray Diffraction; XRD) 24
3.5.2 掃描式電子顯微鏡(Scanning Electron Microscope; SEM) 25
3.6 維氏硬度量測 25
3.7 壓縮試驗 26
第四章 結果與討論 29
4.1 合金元素與球磨方式變化對WVTaTiCr高熵合金的影響 29
4.1.1 Ta、V元素對WVTaTiCr高熵合金的影響 29
4.1.1.1 粉體XRD分析 29
4.1.1.2 塊材SEM與EDS分析 30
4.1.1.3 塊材XRD分析 36
4.1.1.4 維氏硬度分析 37
4.1.2 Ti含量變化與(WVTa)預球磨對WVTaTiCr高熵合金的影響 38
4.1.2.1 粉體XRD分析 38
4.1.2.2 塊材SEM與EDS分析 40
4.1.2.3 塊材XRD分析 45
4.1.2.4 維氏硬度分析 46
4.1.2.5 壓縮試驗 47
4.1.2.6 破斷面分析 48
4.2 WMoVTi耐火中熵合金添加不同黏結相對顯微結構及機械性質的影響 50
4.2.1 粉末XRD分析 50
4.2.2 塊材SEM與EDS分析 53
4.2.3 塊材XRD分析 67
4.2.4 維氏硬度分析 68
4.2.5 壓縮試驗 69
4.2.6 破斷面分析 71
4.3 CoFeNi黏結相添加對不同耐火中熵合金顯微結構及機械性質的影響 74
4.3.1 粉末XRD分析 74
4.3.2 塊材SEM與EDS分析 76
4.3.3 塊材XRD分析 90
4.3.4 維氏硬度分析 91
4.3.5 壓縮試驗 92
4.3.6 破斷面分析 93
4.4 7Ni1.5Co1.5Fe黏結相添加對不同耐火中熵合金顯微結構及機械性質的影響 96
4.4.1 粉末XRD分析 96
4.4.2 塊材SEM與EDS分析 98
4.4.3 塊材XRD分析 112
4.4.4 維氏硬度分析 113
4.4.5 壓縮試驗 114
4.4.6 破斷面分析 116
4.5 黏結相含量變化對WMoVTi中熵合金顯微結構及機械性質的影響 119
4.5.1 CoFeNi黏結相含量變化對WMoVTi中熵合金顯微結構及機械性質的影響 119
4.5.1.1 粉末XRD分析 119
4.5.1.2 塊材SEM與EDS分析 121
4.5.1.3 塊材XRD分析 130
4.5.1.4 維氏硬度分析 131
4.5.1.5 壓縮試驗 132
4.5.1.6 破斷面分析 133
4.5.2 7Ni1.5Co1.5Fe黏結相含量變化對WMoVTi中熵合金顯微結構及機械性質的影響 135
4.5.2.1 粉末XRD分析 135
4.5.2.2 塊材SEM與EDS分析 136
4.5.2.3 塊材XRD分析 146
4.5.2.4 維氏硬度分析 147
4.5.2.5 壓縮試驗 149
4.5.2.6 破斷面分析 151
4.6 Y的添加對WMoVTi中熵合金顯微結構及機械性質的影響 154
4.6.1 粉末XRD分析 154
4.6.2 塊材SEM與EDS分析 155
4.6.3 塊材XRD分析 169
4.6.4 維氏硬度分析 170
4.6.5 壓縮試驗 171
4.6.6 破斷面分析 173
4.7 Mo含量的變化對WMoVTi+7Ni1.5Co1.5Fe合金顯微結構及機械性質的影響 175
4.7.1 粉末XRD分析 175
4.7.2 塊材SEM與EDS分析 176
4.7.3 塊材XRD分析 185
4.7.4 維氏硬度分析 186
4.7.5 壓縮試驗 187
4.7.6 破斷面分析 188
4.8 V、Ti含量的變化對WMoVTi+7Ni1.5Co1.5Fe合金顯微結構及機械性質的影響 191
4.8.1 粉末XRD分析 191
4.8.2 塊材SEM與EDS分析 192
4.8.3 塊材XRD分析 202
4.8.4 維氏硬度分析 203
4.8.5 壓縮試驗 203
4.8.6 破斷面分析 204
第五章 結論 207
5.1 合金元素與球磨方式變化對WVTaTiCr高熵合金的影響 207
5.2 WMoVTi耐火中熵合金添加同黏結相對顯微結構及機械性質的影響 207
5.3 CoFeNi黏結相添加對不同耐火中熵合金顯微結構及機械性質的影響 208
5.4 7Ni1.5Co1.5Fe黏結相添加對不同耐火中熵合金顯微結構及機械性質的影響 208
5.5 黏結相含量變化對WMoVTi中熵合金顯微結構及機械性質的影響 208
5.6 Y的添加對WMoVTi中熵合金顯微結構及機械性質的影響 209
5.7 Mo含量的變化對WMoVTi+7Ni1.5Co1.5Fe合金顯微結構及機械性質的影響 209
5.8 V、Ti含量的變化對WMoVTi+7Ni1.5Co1.5Fe合金顯微結構及機械性質的影響 209
總結 211
參考文獻 213

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