腐蝕環境對航空用7050鋁合金金屬疲勞擧動之影響

以作者查詢圖書館館藏

、以作者查詢臺灣博碩士

、以作者查詢全國書目

、勘誤回報

、線上人數：36

、訪客IP：3.144.42.233

姓名

邵冠璋(Guan-Jhang Shao) 查詢紙本館藏

畢業系所

機械工程學系

論文名稱

腐蝕環境對航空用7050鋁合金金屬疲勞擧動之影響
(Influence of corrosion environment on fatigue behavior of aerospace 7050 aluminium alloy)

相關論文

★ 鋁電解電容器用陽極鋁箔電蝕時電化學舉動之研究	★ 汽車車體用鋁合金板材、擠型材之研究
★ 汽車車體骨架用6000系鋁合金低溫時效與擠型條件之研究	★ 材料製程對汽車車體用鋁合金彎曲加工特性之影響研究
★ 鋁電解電容器用低壓陽極箔鋁箔之研發	★ 鋁原箔對鋁電解電容器用高壓陽極鋁箔電解腐蝕舉動之影響研究
★ 電蝕條件對鋁電解電容器用高壓陽極鋁箔電蝕時電化學舉動之影響研究	★ 鋁原箔製程參數對低壓鋁電解電容器用陽極鋁箔電解腐蝕舉動影響之研究
★ 微量元素對高壓鋁電解電容器用陽極鋁箔電解腐蝕舉動影響之研究	★ 微量元素對低壓鋁電解電容器用陽極鋁箔電解腐蝕舉動影響之研究
★ 製程履歷對汽車車體用6022 鋁合金析出舉動之影響研究	★ 製程條件對汽車車體用6022鋁合金析出擧動之影響
★ 均質化處理及時效處理條件對航空用鋁合金金屬疲勞舉動之影響	★ 鋁電解電容器用高純度鋁箔直流電蝕擧動之模型分析
★ 低壓鋁電解電容器用鋁箔之電蝕條件最佳化研究	★ 比較硬質鋁箔與退火後鋁箔在電蝕時電蝕結構及特性之研究

檔案

[Endnote RIS 格式]

[Bibtex 格式]

[相關文章]

[文章引用]

[完整記錄]

[館藏目錄]

至系統瀏覽論文 ( 永不開放)

摘要(中)

本研究主要以航空用7050鋁合金為實驗材料，探討在不同腐蝕環境條件下(浸泡式腐蝕與開放式腐蝕)所呈現之疲勞裂縫成長特性，以及觀察環境變化對於疲勞裂縫成長加速性的影響。
實驗中藉由改變材料熱處理參數、腐蝕環境參數、頻率參數、應力集中因子振幅參數、加入腐蝕液時之裂縫長度以及R值，並配合光學顯微鏡（OM）、掃描式電子顯微鏡（SEM）、動態材料試驗機作分析，研究影響疲勞裂縫成長特性之因子，搭配合金已知的拉伸性質與應力腐蝕效應，可作為航空材料選用之重要依據。
由實驗結果得知，無論在空氣或腐蝕環境中，當R=0.1及0.8時，合金若實施470℃×24h均質化配合T73處理時，由於塑性變形區較大、裂縫成長路徑較粗糙、鈍化膜較厚，所以裂縫閉合效應較階段均質化配合階段淬水時效處理明顯，使第二階段裂縫成長速率較慢。當環境發生瞬時變化時，裂縫尖端所承受的應力集中因子振幅越大，將有助於腐蝕液進入裂縫尖端，而使疲勞裂縫成長加速性增加。

摘要(英)

A program of experimental and analytical tasks has been conducted to discuss the relationship between corrosion environment(immersion NaCl solution and open flow NaCl solution) and fatigue crack propagation（FCP）in an aluminum aerospace alloy 7050.We observe the influence of environmental change for the accelerating of crack growth rate,too.
The experiment was investigated via different heat treatments, corrosion environments, frequency, stress intensity factor range, crack length of add corrosion solution condition and load ratio. The influence of fatigue crack propagation was characterized and analyzed by using optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Instron Model 8800 Testing System. The basis of airframe structural application is the result of experiment combining with tensile properties and stress corrosion cracking effect.
The result indicate that the alloys received homogenuzation-H470×24h have bigger plastic zone, more rough in crack surface and oxide debris then Step-homogenuzation (StepH) when load ratio (R) are 0.1 and 0.8. So homogenuzation-H470×24h have higher resistance to fatigue crack growth with the crack closure effect. And the accelerating of crack growth rate is changed by stress intensity factor range.

關鍵字(中)

★ 鋁合金
★ 金屬疲勞
★ 腐蝕環境
★ 7050

關鍵字(英)

★ corrosion environment
★ 7050 aluminium alloy
★ fatigue behavior

論文目次

摘要 ...........................................I
ABSTRACT ...........................................II
謝誌 ...........................................III
表目錄..........................................V
圖目錄..........................................VI
第一章緒論.........................................1
一、序言............................................1
二、理論基礎與論文回顧..............................2
2.1 7000系鋁合金之析出強化..........................2
2.2 7000系鋁合金之微結構與腐蝕性的關係..............6
2.3 腐蝕疲勞........................................7
2.4 裂縫閉合現象(crack closure).....................10
第二章本文.........................................12
一、前言............................................12
二、實驗步驟與方法..................................15
2.1 實驗材料的製備..................................15
2.2 疲勞與腐蝕疲勞試驗..............................16
2.3 破斷面之電子顯微鏡(SEM)觀察.....................18
2.4 金相及疲勞裂縫路徑之觀察........................18
三、結果與討論......................................20
3.1 T73與SQA顯微組織差異性之說明....................20
3.2 空氣中的疲勞裂縫成長特性........................21
3.3 腐蝕環境中的裂縫成長............................23
3.4 環境瞬時變化時對疲勞裂縫成長加速性之探討........27
四、結論............................................29
參考文獻............................................31

參考文獻

[1] M. O. Speidel: Stress Corrosion Cracking of aluminum alloys, Metall. Trans. A, vol. 6A, 1975, pp. 631-642.
[2] N. Adler, R. DeIASI and G. Geschwind: Influence of Microstructure on the Mechanical Properties and Stress Corrosion Susceptibility of 7075 Aluminum Alloy, Metall. Trans., vol. 3, 1972, pp.3191-3200.
[3] 楊振國,” 加工熱處理條件對航空用鋁合金之強度及抗應力腐蝕性的影響,”國立中央大學機械工程研究所碩士論文,1997.
[4] G.W. Lorimer and R.B.Nicholson, Acta Met, 14, 1966, p1009~1013.
[5] 菅野幹宏, 歐炳隆：輕金屬, 40(1990), P.672~677.
[6] M. O. Speidel ,M. J. Blackburn ,T. R. Beck and J. A. Feeney ,Corrosion Fatigue：Chemistry , Mechanics ,and Microstructure ,O. F. Devereux ,A. J. McEvily and R. W. Staehle (Eds), Nace,324(1972)
[7] ”Fatigue and Microstructure”Sponsored by the Material Science Division of the American Society for Metals.
[8] C.Laird,in “Fatigue Crack Propagation,”ASTM STP 415,1966,p131
[9] S.P. Lynch: Mechanisms of Intergranular Fracture, Materials Science Forum, vol. 46, 1989, pp. 1-24.
[10] S.P. Lynch: Environmentally assisted cracking-Overview of evidencefor an adsorption-induced localized-slip process, Acta Metall., vol. 36,No. 10, 1988, pp. 2639-2661.
[11] A.J. Sedriks, J. A. S. Green and D. L. Novak: Comparison of theCorrosion and Stress-Corrosion Behavior of a Ternary Al-Zn-Mg Alloy,Metall. Trans., vol. 1, 1970, pp. 1815-1819.
[12] D. Nguyen, A. W. Thompson and I. M. Bernstein: icrostructural Effects on Hydrogen Embrittlement in High Purity 7075 Aluminum Alloy, Acta Metall., vol. 35, 1987, pp. 2417-2425.
[13] W. Elber, “Fatigue Crack Clousure Under Cyclic Tension,” Engineering FractureMechanics, Vol. 2, 1970, pp. 37-45
[14] S. Suresh and R. O. Ritchie, “Propagation of Short Crack,” International MetalsReviews, Vol. 29, 1984, pp. 445-476
[15] 楊智綱,”高強度航空用7000 系鋁合金機械性質、抗應力腐蝕破壞性及銲接熱影響區特性之研究” 國立中央大學機械工程研究所博士論文,2001.
[16] S.Suresh,R.O.Ritchic,Int.Met.Rev.29.1984,455
[17] C. Menzemer, T.S. Srivatsan ,” The effect of environment on fatigue crack growth behavior ofaluminum alloy 5456” ,Materials Science and Engineering A271 (1999) 188–195
[18] Vasudevan AK, Suresh S.”Matall Trans 1982；13A”2271-80
[19] Suresh S, Vasudevan AK, Bretz PE.” Matall Trans 1984；15A”369-79

指導教授

歐炳隆(Bin-Lung Ou)

審核日期

2004-7-14

推文