鋯基非晶質合金具有耐腐蝕特性與良好之機械性質，且有較佳的熱穩定性與玻璃形成能力。又因前人之研究中指出，添加硼元素或矽元素對Zr-Al-Cu-Ni多元塊狀非晶質合金之熱性質有明顯之影響；所以本實驗選擇Zr-Al-Cu-Ni多元塊狀非晶質合金為研究材料，並且同時添加硼元素或矽元素以探討其熱性質之影響。
由實驗之結果顯示，玻璃形成能力指標 g 值以同時添加硼元素含量1 at%與矽元素含量4 at%時為最佳，其值約為0.42；熱穩定性之DTx則以同時添加硼元素含量2 at%與矽元素含量1 at%時最佳，其範圍約在85 K。不論是非恆溫分析法或恆溫分析法，Avrami指數n值範圍皆不具固定值，且活化能都以同時添加硼元素含量1 at%與矽元素含量4 at%時有最高之活化能，其值都大於300 kJ/mol。將Zr60Al7.5Cu17.5Ni10B1Si4試片於721 K以及Zr62Al7.5Cu17.5Ni10B2Si1試片於724 K恆溫熱處理4000秒，使得這兩組試片完全結晶，其中 Zr60Al7.5Cu17.5Ni10B1Si4試片之結晶相為斜方結構的ZrO2相以及正方結構的Zr2Ni相，而Zr62Al7.5Cu17.5Ni10B2Si1試片其結晶相除了為斜方結構的ZrO2相以及正方結構的Zr2Ni相外，還有具有立方結構的Zr2Ni相。由TEM觀察中發現，將Zr62Al7.5Cu17.5Ni10B2Si1試片於694 K恆溫熱處理4000秒後，其非晶質基材中分佈有大小約20 ~40 nm之間的晶粒。

It has been reported that the Zr-based amorphous alloys exhibit high corrosion resistance, good mechanical properties, better thermal stability and good glass-forming ability. The thermal properties of the Zr-Al-Cu-Ni amorphous alloys could be improved by adding boron and silicon that also has been reported. Therefore, the Zr-Al-Cu-Ni amorphous alloys are chosen as the base materials for investigating the effect of the thermal properties by adding boron and silicon at the same time.
According to the results of the experiment, the Zr60Al7.5Cu17.5Ni10B1Si4 amorphous alloy ribbons with the highest GFA index (g value) and the value is 0.42; the maximum supercooled liquid region (DTx) is about 85 K for the Zr60Al7.5Cu17.5Ni10B1Si4 amorphous alloy ribbons. For the isothermal analysis or non-isothermal analysis, the Avrami index (n value) is not constant, and the Zr60Al7.5Cu17.5Ni10B1Si4 amorphous alloy ribbons with the largest activation energy which was more than 300 kJ/mol. When the Zr60Al7.5Cu17.5Ni10B1Si4 amorphous alloy ribbons were heated to 721 K and held for 4000 seconds, the crystallized phases were ZrO2 with orthorhombic structure and Zr2Ni with tetragonal structure. When the Zr62Al7.5Cu17.5Ni10B2Si1 amorphous alloy ribbons were heated to 724 K and held for 4000 seconds, besides the ZrO2 phase with orthorhombic structure and the Zr2Ni phase with tetragonal structure, a Zr2Ni crystallized phase with cubic structure is also included. According to the observation of the TEM image for heating Zr62Al7.5Cu17.5Ni10B2Si1 amorphous alloy ribbons to 694 K and held for 4000 seconds, there are many grains distribute in the amorphous matrix, and the grain size is about 20 ~40 nm.

目錄

目錄..............……….......................….........................................................................I
表目錄................………..................….....................................................................IV
圖目錄….......……………….………………………...................................................V
摘要.......................……………...……...……........................................................ VIII
第一章 前言..........................………..…………………………………........................1
1-1 研究簡介.............………………………..…………………...................1
1-2研究背景.....………………………..…………………..……...................2
第二章 理論基礎.....................…………………………………………........................4
2-1 非晶質合金之製造方法......…………………………….......................4
2-2 非晶質合金之種類與特性...........…….......….........…………………..5
2-2-1 非晶質合金之種類.............................……….………………....5
2-2-2 非晶質合金之特性.........................…..………………………...6
2-2-2-1 機械性質......………………...….....……..…...............7
2-2-2-2 磁性質..............……………………...……..................7
2-2-2-3 耐蝕性................................……………………….…..8
2-2-2-4 其他性質...........................…………………….…...…8
2-3 非晶質合金之形成條件.............................…………………………....9
2-3-1 實驗歸納法則.................................……………………...……..9
2-3-2 相關理論.......….........................…………………….………...10
2-4 非晶質合金之熱力學性質.....................……………………………...14
2-4-1 非晶質之平衡...............................…………….……………....14
2-4-2 玻璃轉換溫度(Tg) ....……………………...……......................15
2-4-3 簡化玻璃轉換溫度(Trg) ....……………….…....……...............16
2-5熱力學分析......………..............................…………………….……....17
2-5-1 恆溫分析法.................................………………………….…..17
2-5-2非恆溫分析法........................….....………………….………..19
2-5-2-1 一般之非恆溫分析法......……...……….……………19
2-5-2-2 修正之非恆溫分析法.................……………………..22
第三章 實驗方法...........................................…………………...…………………....25
3-1 合金試片之準備..............................….......…………..……………….25
3-1-1 合金之配製....................................……………….…………...25
3-1-2 電弧熔煉(Arc-Melting)與墬落式鑄造(Drop-Casting)……….25
3-1-3 合金薄帶之製作..............................……………….………….26
3-2 微觀組織分析........................................…………………….………..26
3-2-1 XRD繞射分析.............................….………………………...27
3-2-2 掃描式電子顯微鏡(SEM)觀察與能譜元素(EDS)分析……....27
3-2-3 穿透式電子顯微鏡(TEM)觀察與擇域繞射(SAD)分析……...27
3-3 熱分析.......................................……………………………….….......28
3-3-1熱分析儀(DTA)................................……………………….…..28
3-3-2微熱差分析儀(DSC) ........................………………………......28
第四章 實驗結果.............………………................………………………...…….......30
4-1 試片外觀觀察……….........…….....…………………….…….…........30
4-2 X光繞射分析……………...................….……………………...….......31
4-3 非恆溫熱力學和動力學分析....……………...………………………..31
4-4 恆溫熱力學和動力學分析....……………..…...……..………………..34
4-5 SEM觀察與EDS分析..………………..…….....……..………………..35
4-6 TEM觀察與EDS分析…………...………………………..……….......36
第五章 分析與討論....………………................…………………………....…….......37
5-1 熱力學和動力學分析…................………………….…………….......37
5-1-1 非恆溫分析法…................………………….………….......37
5-1-2 恆溫分析法…................………………….………...……......39
5-2 X光繞射分析…................………………………….……….....……....40
5-3 TEM觀察..……………………………..…………….……………........41
第六章 結論..........…….....……………………...….……………………..……….......42
參考文獻............................................………………………………….........…….....44
表..........................................................……………………………………………....50
圖.............................................................…………………………………….………59







表目錄

表1-1 非晶質合金之特性...........................………………...……...……..............50
表2-1 最初非晶質合金之系統分類...........................…………………………….51
表2-2 多元系塊狀非晶質合金種類與發展歷程.............…...….…...……………52
表2-3 多元系塊狀非晶質合金之成分分類......................…….………………....53
表2-4 非晶質合金之磁特性................................……………….……………......54
表2-5 非晶質合金之決定因子....................................……..…….………………55
表3-1 Zr65-X-YAl7.5Cu17.5Ni10BXSiY合金薄帶各組成元素之比例..….......…….…56
表4-1 Zr65-X-YAl7.5Cu17.5Ni10BXSiY合金薄帶各種溫度與指標........……..............57
表4-2 Zr65-X-YAl7.5Cu17.5Ni10BXSiY合金薄帶各組成元素之分析比例.…….........58











圖目錄

圖1-1 結晶與非晶質之原子排列方式.....…….….…………...….........................59
圖1-2 Zr55Cu30Al10Ni5之室溫機械行為 (a)完全非晶質 (b)部分結晶……….....59
圖1-3 撞擊激冷法示意圖....................................…………...………………...….60
圖1-4 雙輪連續急冷示意圖..................................…………………………….....60
圖1-5 激冷融液旋噴法示意圖...................................………..…………………..61
圖1-6 平面流鑄法示意圖...................................……...…………………..……...61
圖2-1 合金系統之分類圖.......................……………..………………..................62
圖2-2 結晶與非結晶之x光繞射結果......................……..………………………..62
圖2-3 施加外力於非晶質材料，原子對力之傳導方式.......……........…….……..63
圖2-4 非晶質合金之形成法則..............…….…………….……….………...........63
圖2-5 玻璃形成時，焓與比容之關係圖..........................………….……………..64
圖2-6 Zr59Al7.5Ni10Cu17.5B6非晶質合金之DSC曲線.....…………….……............64
圖2-7 非晶質比熱與溫度之關係圖.................…………...………….…..............65
圖2-8 臨界冷卻速率與玻璃形成能力關係圖......................………….………….65
圖2-9 三種空間成長機制....…………........................………………….………...66
圖3-1 實驗流程圖......……......................................…………………….………..67
圖3-2 實驗流程圖 (a)真空熔煉爐 (b)冰水冷卻機之外觀圖......……….…..…..68
圖3-3 真空電弧熔煉爐之構造圖......……………….………………...…….……..69
圖3-4 墬落式鑄造爐之構造圖...............……………………..……….....…..........70
圖3-5 激冷旋噴熔煉爐之外圖......….......................................................…….....71
圖3-6 升溫方式示意圖 (a)非恆溫過程 (b)恆溫過程….……….........……….....72
圖4-1 Zr65-X-YAl7.5Cu17.5Ni10BXSiY合金薄帶之外觀圖與製作示意圖………..…73
圖4-2 Zr65-X-YAl7.5Cu17.5Ni10BXSiY合金薄帶X光繞射分析..…....….......……......74
圖4-3 Zr65-X-YAl7.5Cu17.5Ni10BXSiY合金薄帶不同升溫速率之DSC結果………...75
圖4-4 Zr65-X-YAl7.5Cu17.5Ni10BXSiY合金薄帶真實玻璃轉換溫度與結晶溫……..78
圖4-5 Zr65-X-YAl7.5Cu17.5Ni10BXSiY合金薄帶之Tx與 g 值…............….…….......78
圖4-6 Zr60Al7.5Cu17.5Ni10B1Si4與Zr62Al7.5Cu17.5Ni10B2Si1合金薄帶之結晶度與
恆溫時間關係圖..........................……………………………………….......79
圖4-7 Zr60Al7.5Cu17.5Ni10B1Si4合金薄帶之結晶度與恆溫時間關係圖……….....80
圖4-8 Zr60Al7.5Cu17.5Ni10B1Si4與Zr62Al7.5Cu17.5Ni10B2Si1合金薄帶之
BEI影像…………………..………………….…..…………………………..81
圖4-9 Zr60Al7.5Cu17.5Ni10B1Si4與Zr62Al7.5Cu17.5Ni10B2Si1合金薄帶之
Mapping結果..........................…….……………………………………......82
圖4-10 Zr60Al7.5Cu17.5Ni10B1Si4合金薄帶之TEM分析
(a)明視野影像 (b)暗視野影像 (c)擇域繞射圖…………...……….…..…84
圖4-11 Zr60Al7.5Cu17.5Ni10B2Si1合金薄帶之TEM分析
(a)明視野影像 (b)暗視野影像 (c)擇域繞射圖………….………….……85
圖5-1 Zr65-X-YAl7.5Cu17.5Ni10BXSiY合金薄帶
ln[-ln(1-x)]對lnf作圖..........…………......…...…………………..…….......86
圖5-2 Zr65-X-YAl7.5Cu17.5Ni10BXSiY合金薄帶
ln[-ln(1-x)]對1/T作圖......……………….………………………….………89
圖5-3 Zr65-X-YAl7.5Cu17.5Ni10BXSiY合金薄帶成核飽和點之結晶度.…….……....92
圖5-4 Zr60Al7.5Cu17.5Ni10B1Si4與Zr62Al7.5Cu17.5Ni10B2Si1合金薄帶之
DSC結果…………………………..………………………………….…......93
圖5-5 Zr60Al7.5Cu17.5Ni10B1Si4與Zr62Al7.5Cu17.5Ni10B2Si1合金薄帶之
n值對溫度作圖…….………………………………………………………..94
圖5-6 Zr60Al7.5Cu17.5Ni10B1Si4與Zr62Al7.5Cu17.5Ni10B2Si1合金薄帶之
ln[-ln(1-x)]對1/T作圖………….…………....……………………...………95
圖5-7 Zr60Al7.5Cu17.5Ni10B1Si4與Zr62Al7.5Cu17.5Ni10B2Si1合金薄帶成核與成長
活化能關係圖…………….……………………….…..……………...………96
圖5-8 Zr60Al7.5Cu17.5Ni10B1Si4與Zr62Al7.5Cu17.5Ni10B2Si1合金薄帶
ln[-ln(1-x)]對1/T作圖…………...………………………….……....………97
圖5-9 Zr60Al7.5Cu17.5Ni10B1Si4與Zr62Al7.5Cu17.5Ni10B2Si1合金薄帶
lnt對1/T做圖...………………...…………………………….……....………98
圖5-10 Zr60Al7.5Cu17.5Ni10B1Si4合金薄帶lnt對1/T做圖
(a)低溫 (b)高溫…………...………….……...…...…….….……….………99
圖5-11 Zr60Al7.5Cu17.5Ni10B1Si4與Zr62Al7.5Cu17.5Ni10B2Si1合金薄帶
恆溫之X光繞射分析………..………...…….…..…...….……….…………100
圖5-12 Zr60Al7.5Cu17.5Ni10B1Si4與Zr62Al7.5Cu17.5Ni10B2Si1
恆溫之結晶X光繞射分析……….....……..………..………………………101
圖5-13 熱處理後Zr60Al7.5Cu17.5Ni10B2Si1合金薄帶之TEM影像
(a)明視野影像 (b)擇域繞射圖………………..…...…………..…………102

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