臺灣博碩士論文加值系統

目前AA7005鋁合金之熱處理製程皆是延用Al-Zn-Mg-Cu合金者，僅予以小幅的修改，是否適用於含銅量極低（<0.1%）之AA7005鋁合金，有待商榷，且在文獻上有關AA7005鋁合金熱處理製程的研究亦很有限。故本研究的目的即為探討熱處理製程對AA7005鋁擠型材的抗應力腐蝕性能的影響，並找尋合適之熱處理製程，使其具有高強度和高抗應力腐蝕性的組合。
在本研究中將針對AA7005鋁合金之固溶溫度與時間、時效溫度與時間以及自然時效天數對於後續熱處理之影響進行探討，找出適用於AA7005鋁合金之T6、T73熱處理製程參數組合，及抗拉強度與硬度值間之關連性，據以作為後續RRA熱處理的強度參考指標。並且進行RRA製程參數值的探討。將已完成T6煉度時效處理的AA7005鋁合金在200℃，190℃ ，180 ℃及170 ℃等四種退化處理溫度進行時間不等的退化處理後，再進行T6時效處理。隨後將完成RRA熱處理之試塊製做硬度試片及Bent-Beam試片，進行硬度、導電度量測及應力腐蝕試驗，尋求適用於AA7005鋁擠型材之RRA熱處理製程參數組合。
實驗結果顯示，AA7005鋁合金之最佳固溶溫度時間為470℃/40min，且在人工時效前施以自然時效18天，將可有效達到最佳析出強化效果。最佳T6熱處理製程參數為470℃/40min＋自然時效/18天＋120℃/40∼ 42hr.，可達到之最大抗拉強度值為376.6Mpa，最大硬度值為HRB71。最佳之T73過時效熱處理製程參數組合為470℃/40min＋自然時效/18天＋107℃/8hr.＋168℃/19hr.。最佳RRA熱處理之退化處理參數組合分別為200℃/10min，190℃/40min，180℃/1hr.40min及170℃/4hr.20min。經四種退化處理參數組合之RRA熱處理試片其強度均可達T6之強度，其導電度值皆與T73煉度導電度值相近；且抗應力腐蝕性則近於T73之抗應力腐蝕性能。顯示RRA熱處理確實可適用於7005鋁擠型材，使其擁有T6強度及近於T73之的抗應力腐蝕性。

第一章 前言 1
第二章 文獻探討 5
　2.1 鋁合金之分類 5
　2.2 鋁合金性質狀態命名 7
　2.3 7000系鋁合金之析出強化 8
　2.4 應力腐蝕破壞簡介 14
　2.5 7000系鋁合金應力腐蝕破壞的機構 17
　2.6 RRA熱處理 21
　2.7 添加合金元素之影響 28
第三章 實驗方法 29
　3.1 實驗流程 29
　3.2 實驗材料 31
　3.3 熱處理流程 33
3.4 金相顯微組織觀察 38
3.5 穿透式電子顯微鏡（TEM）觀察 38
　3.6 拉伸試驗 38
3.7 導電度量測 41
　3.8 硬度試驗 42
　3.9 應力腐蝕測試 42
第四章 結果與討論 46
　4.1 固溶溫度之影響 46
　4.2 自然時效對後續人工時效之影響 48
　4.3 T6頂時效與T73過時效熱處理製程 50
　4.4 RRA熱處理 58
第五章 結論 74

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