顧鈞豪臺灣大學：材料科學與工程學研究所吳佳龍Wu, Chia-LungChia-LungWu2007-11-262018-06-282007-11-262018-06-282005http://ntur.lib.ntu.edu.tw//handle/246246/55272本研究有兩大部分，第一部分是利用微電漿對厚度僅有0.076mm 之AM350 不鏽鋼箔片進行銲接，並求出AM350 箔片微電漿銲接製 程之最佳銲接參數，另外再搭配不同的銲前、銲後熱處理，可獲得 AM350 箔片銲件最佳熱處理條件。第二部分的研究則是進行AM350 波紋片之模擬試銲，並以銲接峰值電流為變數，以期求得最佳的 AM350 波紋片銲接參數。 研究結果顯示，當銲接峰值電流為2.5A，而銲接走速為7.5in/min時，可獲得最佳品質的AM350 不鏽鋼箔片銲件。另外，不論銲前熱 處理狀態為何，AM350 箔片銲件之機械性質主要取決於銲後熱處 理；若銲件未進行銲後熱處理，其拉伸強度呈現最低（僅約100MPa 左右），且熔融區內δ→γ的相變態會因為高達4.52 ×104 °C /sec 的冷卻速率，而具有Massive Transformation 的特性；若銲前及銲後皆施行SCT850 時效處理（455℃，持溫3 小時）之箔片銲件，其拉伸強度值最高（158MPa），但延伸率僅有2∼3%；當銲後時效溫度提升至535℃以上時，箔片銲件拉伸強度值會隨著之降低，但具有相當不錯的延伸率（約6∼8%）。 對於波紋片銲件的研究成果，當銲接峰值電流設定在4A~5A 間時，具有圓弧狀的銲道外觀，可獲得最佳的銲接品質。This investigation included two major parts. The first was to develop the optimal welding parameters and heat treatment conditions for AM350 stainless steel foil welds with a thickness of 0.076mm. The second was to simulate the plasma arc welding process and establish the appropriate welding parameters for AM350 bellow weldments. Results of this investigation revealed that AM350 foil welds would have the optimum qualities as the peak current and welding speed were fixed at 2.5A and 7.5in/min respectively. The tensile properties of foil specimens, regardless of their former heat treatment conditions, were determined by the post-heat treatment. The foil weldments without post-heat treatment had the minimum tensile strength, only 100MPa, and the solid-state phase transformation of δ→γwas found to be via massive transformation due to its extremely high cooling rate of 4.52 ×104 °C /sec . The foil specimens subjected to the SCT850 heattreatment before and after welding performed the highest tensile strength of 158MPa, but with a quite low elongation. The elongation of the foil welds would be substantially increased as the aging temperature was raised to 535℃. For bellow welds, while the peak current was set between 4A and 5A, the shape of the weld pool would appear a continuous circular, which could homogeneously distribute the stress on the welds.中 文 摘 要...................................................................................................................i Abstract ...........................................................................................................................i 目 錄.............................................................................................................................i 圖 目 錄...................................................................................................................iv 表 目 錄..................................................................................................................xv 第一章 前言..................................................................................................................1 第二章 基本理論與文獻回顧......................................................................................4 2–1 AM350 半沃斯田鐵系析出硬化型不鏽鋼之物理冶金特性.......................4 2–2 AM350 固化理論.........................................................................................11 2–3 銲接熱裂縫的成因.....................................................................................19 2–3–1 銲接金屬區（Weld Metal）熱裂縫理論......................................19 2–3–2 熱影響區熱裂縫理論（Heat–Affected Zone Liquation Cracking） ......................................................................................................................23 2–3–3 肥粒鐵對於AM350 不鏽鋼與熱裂縫的影響...............................23 2–3–4 AM350 銲接特性　.........................................................................27 2–4 微電漿銲接及基本原理.............................................................................28 2–4–1 電漿銲接基本原理..........................................................................29 2–4–2 電漿電弧銲之銲接參數..................................................................32 第三章 實驗方法與步驟............................................................................................34 ii 3–1 實驗步驟流程圖..........................................................................................34 3–2 實驗材料......................................................................................................34 3–3 微電漿銲接設備與夾治具的設計..............................................................34 3–3–1 AM350 鋼箔之法蘭式微電漿銲接.................................................34 3–3–2 AM350 鋼箔之波紋片微電漿銲接.................................................35 3–4 熱處理規劃..................................................................................................41 3–5 顯微組織觀察..............................................................................................44 3–5–1 光學顯微組織觀察..........................................................................44 3–5–2 掃瞄式電子顯微鏡顯微組織觀察..................................................44 3–5–3 電子探針微區分析儀......................................................................44 3–6 X光繞射分析...............................................................................................45 3–7 機械性質.....................................................................................................45 3–7–1 拉伸試驗與拉伸標準試片模具製作..............................................45 第四章 結果與討論....................................................................................................47 4–1 AM350 原材與熱處理分析.........................................................................47 4–1–1 AM350 原材成分分析.....................................................................47 4–1–2 AM350 原材與進行熱處理後之顯微結構及X光繞射分析結果..47 4–1–3 AM350 原材及經不同熱處理後之拉伸試驗.................................59 4–2 法蘭式箔片銲接參數之決定與銲接品質.................................................64 4–2–1 銲接峰值電流對銲道寬度的影響.................................................64 4–2–2 銲速對銲道寬度的影響.................................................................71 4–2–3 法蘭式箔片微電漿銲接參數決定之拉伸試驗.............................73 iii 4–2–4 法蘭式箔片銲件之銲前與銲後熱處理試驗.................................77 4–3 波紋片微電漿銲接與銲接品質...............................................................133 4–3–1 波紋片銲道形狀分析....................................................................136 4–3–2 峰值電流對波紋片銲道熔深的影響............................................142 4–3–3 波紋片銲件顯微結構觀察............................................................144 第五章 結論..............................................................................................................147 未來研究方向............................................................................................................149 第六章　參考文獻....................................................................................................15025798409 bytesapplication/pdfen-US半沃斯田鐵系析出硬化行不鏽鋼微電漿銲接波紋片波紋管AM350PAWbellowsthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/55272/1/ntu-94-R92527067-1.pdf