Stellite 合金為兼具高硬度、耐磨耗、抗腐蝕及耐高溫的鈷基合金,因此常應用在較嚴苛的環境中,如刀具、模具、高溫閥門等。
但 Stellite 合金成本高,本研究目的即為開發成本較低的新型高熵合金,並使其性質與 Stellite 媲美而有取代的機會。
結果顯示本研究所開發的合金展現出優異的抗腐蝕性、抗氧化能力及抗磨耗能力且擁有高硬度,優於 Stellite,深具應用的潛力。

Stellite is a series of cobalt-base alloy which has high hardness, wear and corrosion resistance, and high-temperature properties.
Thus, stellite alloys are typically used in severe conditions encountered by cutting tools, molds, valves, etc.
In this research, we want to develop new and cheaper high entropy
alloys which have excellent properties better than Stellite.
The results show that we successfully develop a series of alloys with
outstanding resistance to corrosion, oxidation, and wear.
Overall performance of these alloys is better than Stellite.
Thus, these high-entropy alloys own their potential in various severe applications.

摘 要 I
Abstract II
致謝 III
目錄 VI
圖目錄 XII
表目錄 XVIII
壹、 前言 1
貳、 文獻回顧 3
2.1 超合金 3
2.2 介金屬化合物 5
2.2.1 電子化合物 5
2.2.2 σ相簡介 8
2.3 Stellite 合金 9
2.4 高熵合金 13
2.4.1 高熵合金開發背景 13
2.4.2 高熵合金的特色 15
參、 實驗方式 23
3.1 成分設計與流程 23
3.1.1 合金製備與設計 23
3.1.2 實驗流程 25
3.1.3 真空電弧熔煉 25
3.2 X-ray繞射分析 26
3.2.1 時效處理 26
3.3 微結構觀察與成分分析 27
3.4 硬度與破裂韌性量測 27
3.5 密度測量 28
3.6 擦損磨耗 29
3.7 腐蝕浸泡試驗 30
3.8 室溫磨耗試驗 30
3.9 高溫磨耗試驗 31
3.10 氧化增重試驗 32
3.11 高溫硬度量測 32
3.12 熱膨脹係數量測 33
肆、 結果與討論 34
4.1 Stellite 1系列基地相變量高熵合金與Stellite微結構 34
4.1.1 Stellite 1 35
4.1.2 ST1-60.5 39
4.1.3 ST1-55.5 43
4.1.4 ST1-54.7 47
4.1.5 ST1-50.5 52
4.1.6 ST1系列高熵合金與Stellite1機械性質比較 56
4.2 Stellite 6系列基底變量高熵合金與Stellite微結構 58
4.2.1 Stellite 6 60
4.2.2 ST6-M 64
4.2.3 ST6-69 68
4.2.4 ST6-64 72
4.2.5 ST6-61.5 76
4.2.6 ST6-60.25 81
4.2.7 ST6-59 85
4.2.8 ST6基地相變量系列高熵合金與Stellite6機械性質比較 90
4.3 Stellite 6系列元素變量高熵合金微結構 93
4.3.1 ST6-64+C 95
4.3.2 ST6-69+2C 99
4.3.3 ST6-69+2.5C 103
4.3.4 ST6-Cr40 107
4.3.5 ST6-Ni35 111
4.3.6 ST6-Ni35-2 115
4.3.7 ST6-Ni30 119
4.3.8 ST6-Ni25 123
4.3.9 ST6-Ni25-2 127
4.3.10 ST6元素變量系列高熵合金與Stellite6機械性質比較 131
4.4 Stellite 21系列元素變量高熵合金微結構 134
4.4.1 Stellite 21 135
4.4.2 B61 139
4.4.3 B61-2 143
4.4.4 B61-3 146
4.4.5 B66 151
4.4.6 B66-2 155
4.4.7 B66-3 159
4.4.8 B66-4 163
4.4.9 B66-5 167
4.4.10 B66改良系列機械性質討論 172
4.4.11 B系列高熵合金與Stellite 21機械性質比較 175
4.5 室溫磨耗性質測試 178
4.5.1 Stellite 6與ST6系列之室溫磨耗 178
4.6 擦損磨耗性質測試 185
4.6.1 Stellite 6與ST6系列之擦損磨耗性質 185
4.7 高溫磨耗性質測試 188
4.7.1 Stellite6與Ni25之高溫磨耗性質 188
4.8 衝磨測試 190
4.9 時效熱處理 190
4.9.1 Stellite 21與B66-2、B66-5 之時效熱處理 190
4.10 腐蝕浸泡實驗 193
4.10.1 室溫下浸泡5%HCl 193
4.10.2 室溫下浸泡10%H2SO4 194
4.10.3 室溫下浸泡10%HNO3 195
4.10.4 80°C下浸泡5%HCl 196
4.10.5 80°C下浸泡10% H2SO4 197
4.10.6 80°C下浸泡10% HNO3 198
4.11 氧化增重實驗 199
4.11.1 Stellite 6與Ni25合金於1000°C之氧化增重 199
4.12 高溫硬度實驗 201
4.12.1 Stellite與Ni25之高溫硬度性質 201
4.12.2 Stellite21和B66-5高溫硬度性質 204
4.13 熱膨脹係數測試 206
4.14 導電度測試 207
伍、 結 論 208
陸、 本研究貢獻 211
柒、 建議未來研究方向 212
捌、 參考文獻 213

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