本實驗使用摩擦攪拌銲接方法來使Si粒子打細打散，並利用高溫攪拌的過程改善微結構使機械性質提升。由不同轉速1400rpm、700rpm、350rpm，85mm/min，一道次的硬度值可得知，轉速愈高硬度值愈高。對不同走速120mm/min、85mm/min、45mm/min而言，走速愈快硬度值愈高，但道次對本實驗沒有明顯影響。由拉伸試驗可知，經過摩擦攪拌後延展性皆有大幅的提升，由原始的0.9%上升至15%，所以摩擦攪拌製程將Si粒子的散佈均勻，對於延展性的提升有很大的幫助。而固溶熱處理和時效處理也對於微結構有重大的影響，使得強度有明顯的提升。經固溶處理使合金元素固溶量變多，溶質可以重新析出而較小；時效處理可將溶質大量析出因而造成析出硬化效果，經過固溶後以 1400rpm-45mm/min-1道次、時效8小時的結果，拉伸強度可達360MPa和原始材料的159MPa相比上升非常多。本實驗隨著攪拌參數和不同熱處理條件對於材料強度有重大的影響，延展性也因經由摩擦攪拌製程(FSP)後而有大幅改善。

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總目錄………………………………………………….……………….Ⅰ
圖目錄………………………………………………….……………….Ⅴ
表目錄………………………………………………….……………….Ⅹ
一、前言………………………………………………………………….1
二、文獻回顧…………………………………………………………….3
2.1摩擦攪拌銲接和製程介紹……………………………………...3
2.1.1工具頭的影響……………………………………………..4
2.1.2影響FSP的因素………………………………………….5
2.2 FSP時材料流動的形態和溫度分佈…………………………...6
2.2.1材料在FSP時的流動情形………………………………..6
2.2.2溫度分佈…………………………………………………..9
2.3微結構的發展………………………………………………….10
2.3.1攪拌區(stirred or nugget zone)…………………………..10
2.3.2熱機影響區(Thermo-mechanically affected zone)……...12
2.3.3熱影響區(Heat-affected zone)…………………………...12
2.4經過FSP後的材料性質………………………………………13
2.4.1殘餘應力…………………………………………………13
2.4.2硬度………………………………………………………14
2.4.3拉伸強度和延展性………………………………………15
2.5Al-Si合金………………………………………………………16
2.5.1 Al-Si合金的基本介紹…………………………………..17
2.5.2 Al-Si合金經過FSP的性質…………………………….18
2.5.3 AC8A的成份和微結構發展……………………………23
三、實驗方法……………………………………………………………25
3.1材料…………………………………………………………….25
3.2實驗過程……………………………………………………….25
3.2.1摩擦攪拌銲接製程………………………………………25
3.2.2熱處理……………………………………………………26
3.3微結構分析…………………………………………………….26
3.3.1離子拋光機(ion polish)………………………………….26
3.3.2光學顯微鏡觀察(OM)…………………………………...26
3.3.3掃描式電子顯微鏡觀察(SEM)………………………….27
3.3.4穿透式電子顯微鏡(TEM)……………………………….28
3.4機械性質……………………………………………………….29
3.4.1微硬度試驗………………………………………………29
3.4.2拉伸試驗…………………………………………………30
四、結果…………………………………………………………………31
4.1原始AC8A的微結構觀察和硬度值………………………….31
4.2摩擦攪拌製程參數對硬度值和微結構觀察………………….31
4.2.1轉速的變化………………………………………………31
4.2.2走速的變化………………………………………………33
4.2.3道次的變化………………………………………………34
4.3熱處理對硬度值和微結構的影響…………………………….35
4.3.1原始AC8A經過熱處理的硬度值變化…………………35
4.3.2 FSP前固溶及後時效處理對於高轉速攪拌之影響……36
4.3.3 FSP前固溶及後時效處理對於低轉速攪拌之影響……38
4.4 拉伸試驗結果…………………………………………….......39
4.4.1摩擦攪拌製程不同參數拉伸結果………………………40
4.4.2熱處理對摩擦攪拌製程拉伸結果………………………40
4.5 TEM結果……………………………………………………...41
五、討論…………………………………………………………………43
5.1摩擦攪拌製程參數的影響…………………………………….43
5.2熱處理的影響………………………………………………….44
5.3摩擦攪拌製程對AC8A的強化機制…………………………45
5.3.1晶界強化…………………………………………………45
5.3.2 Orowan強化……………………………………………..46
5.4 Si粒子大小的影響……………………....................................47
5.5經摩擦攪拌製程TEM分析…………………………………..48
六、結論…………………………………………………………………51
參考文獻………………………………………………………………..53
圖………………………………………………………………………..56
表………………………………………………………………………..91

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