跳到主要內容

臺灣博碩士論文加值系統

(3.87.33.97) 您好!臺灣時間:2022/01/27 17:33
字體大小: 字級放大   字級縮小   預設字形  
回查詢結果 :::

詳目顯示

: 
twitterline
研究生:鍾昆原
論文名稱:7005擠製鋁合金的拉伸與疲勞性質研究
指導教授:施 登 士
學位類別:碩士
校院名稱:國立中央大學
系所名稱:機械工程研究所
學門:工程學門
學類:機械工程學類
論文種類:學術論文
論文出版年:2002
畢業學年度:90
語文別:中文
中文關鍵詞:7005多角化動態回復動態再結晶可靠度
外文關鍵詞:7005poligonizationdynamic recoverydynamic recrystallizationreliability
相關次數:
  • 被引用被引用:20
  • 點閱點閱:783
  • 評分評分:
  • 下載下載:229
  • 收藏至我的研究室書目清單書目收藏:0
本研究的主要目的在於探討鋁合金7005擠製件的拉伸與疲勞性質。
在拉伸性質方面,討論高應變速率(1.85x10-2 s-1)及低應變速率(1.85x10-4 s-1)對拉伸強度、降伏強度及伸長率的影響,分析微結構變化對拉伸性質造成的差異。實驗結果顯示,高應變速率下應變硬化效果顯著,得到較高的拉伸強度及降伏強度;低應變速率下由於動態回復的多角化過程,得到次晶粒受應力作用拉長,因此有較高的伸長率。
疲勞性質方面,分析兩種高低反覆應力(240 MPa、180 MPa)的破壞模式與微結構改變之間的關係。實驗結果顯示,存在於試棒表面附近的介在物顆粒對疲勞壽命有很大的影響。在塑性變形過程中,若發生動態回復、多角化的現象,使晶粒軟化,疲勞裂縫呈現穿晶破壞模式,出現疲勞紋;若發生動態再結晶的現象,會出現細小的晶粒,疲勞裂縫呈現沿晶破壞,可以看到粗糙的破壞表面。最後利用可靠度統計分析中常用的韋伯分布函數來討論疲勞的破壞機率,並做疲勞壽命預測。
The aim of this study was to investigate the tensile and fatigue properties of as- extruded aluminum alloy, 7005.
Regrading to tensile properties, specimens were tested at higher strain rate (1.85x10-2 s-1) and lower strain rate (1.85x10-4 s-1) and showed the effects on the UTS, YS and elongation. As the experimental results indicated, the strain hardening effect under higher strain rate was more obvious and both the UTS and YS were higher. The polygonization of dynamic recovery under lower strain rate deformation resulted in subgrains stretched by tensile stress. So the elongation was higher, too.
In the part of fatigue property, the relationship between fractography and microstructure of specimens under two levels of repeated stress(240 MPa、180 MPa) was analyzed. As the experimental results indicated, the existent inclusion particles near specimen surface had a great influence on fatigue life. During the plastic deformation process, if dynamic recovery and polygonization occurred in the specimens, the grains were softened and the fatigue crack was transgranular fracture. Then the fatigue striations showed. If dynamic recrystallization occurred, the microstructure showed fine grains and the fatigue crack was intergranular fracture. The rough fracture surface was observed. Finally the statistical analysis of reliability, Weibull distribution function, was utilized to predict the fracture probability and fatigue life.
摘要…………………………………………………………………………………Ⅰ
Abstract……………………………………………………………………………Ⅱ
總目錄………………………………………………………………………………Ⅲ
表目錄………………………………………………………………………………Ⅴ
圖目錄………………………………………………………………………………Ⅳ
第一章 前言…………………………………………………………………….1
第二章 文獻介紹……………………………………………………………….2
2-1 鋁合金材料特性簡介……………………………………………………….2
2-2 鋁合金的分類……………………………………………………………….2
2-3 鍛造用鋁合金的特性……………………………………………………….3
2-4 鋁的FCC晶格結構………………………………………………………….6
2-5 拉伸試驗…………………………………………………………………….6
2-5-1 萬能試驗機…………………………………………………………….6
2-5-2 拉伸試驗應力分析…………………………………………………….6
2-5-3 真應力-真應變曲線……………………………………………………7
2-6 高週疲勞試驗……………………………………………………………….8
2-6-1 疲勞破壞……………………………………………………………….8
2-6-2 疲勞破壞之形貌特徵………………………………………………….8
2-6-3 旋轉樑疲勞試驗機之原理…………………………………………….9
2-6-4 疲勞應力分析………………………………………………………….9
2-7 韋伯分布在工程上的應用…………………………………………………12
第三章 理論探討………………………………………………………………13
3-1 疲勞裂縫起始與成長機構…………………………………………………13
3-1-1 疲勞裂縫起始機構……………………………………………………13
3-1-2 疲勞裂縫成長機構……………………………………………………13
3-1-3 疲勞試棒最後破斷處…………………………………………………14
3-2 可靠度和破壞機率分析:韋伯分布函數…………………………………14
3-3 動態回復(Dynamic Recovery ) …………………………………………16
3-4 動態再結晶(Dynamic Recrystallization) ……………………………17
第四章 實驗方法與步驟………………………………………………………19
4-1 實驗材料……………………………………………………………………19
4-2 實驗試棒之規格與準備……………………………………………………19
4-3 實驗儀器……………………………………………………………………19
4-4 實驗步驟……………………………………………………………………20
4-5 韋伯分布函數預測不同破壞機率下疲勞轉數……………………………21
第五章 結果與討論……………………………………………………………23
5-1 鋁合金7005擠製圓棒的微結構特徵…………………………………….23
5-2 拉伸試驗結果分析…………………………………………………………24
5-2-1 鋁合金7005的拉伸性質…………………………………………….24
5-2-2 鋁合金7005的拉伸破壞分析……………………………………….24
5-3 疲勞試驗結果分析…………………………………………………………26
5-3-1 鋁合金7005的疲勞性質…………………………………………….26
5-3-2 鋁合金7005的疲勞裂縫起始……………………………………….27
5-3-3 鋁合金7005的疲勞裂縫成長與破壞分析………………………….28
5-4 介在物顆粒對鋁合金7005的疲勞壽命影響…………………………….29
5-5 鋁合金7005的疲勞壽命預測…………………………………………….30
5-6 綜合討論……………………………………………………………………31
第六章 結論……………………………………………………………………33
參考文獻……………………………………………………………………………34
1. 黃振賢, “機械材料”, 文京圖書股份有限公司, 新竹, 民國69年, 第311~
331頁。
2. 賴耿陽, “非鐵金屬材料”, 復漢出版社, 台北, 民國71年, 第151~168頁。
3. ASM, “Aluminum Alloys”, Metals Handbook 8th Edition, Vol.8, 1976,
pp.261.
4. ASM, “Aluminum Alloys”, Metals Handbook 8th Edition, Vol.8, 1976,
pp.265.
5. Gurbuz R, Alpay S.P., “Effect of coarse second phase particle on
fatigue crack propagation of an Al-Zn-Mg-Cu alloy”, Scripta Metallurgica et Matenrialia, V30 n11, Jun 1 1944, pp.1373~1376
6. Robert E. Reed-Hill, “Slip System in Different Crystal Forms”,
Physical Metallurgy Principles, 3th Edition, 1994, pp.140~146.
7. R. W. Cahn and P. Haasen, “Crystal Structures of The Metallic
Elements”, Physical Metallurgy, Third revised and enlarged edition,
1983, pp.50~60.
8. 陳永增,鄧惠源, “機械材料試驗”, 高立出版社, 台北, 民國86年, 第83~98
頁。
9. ASM, “Introduction to Tensile Testing”, Metals Handbook 8th Edition,
Vol.8, 1976, pp.
10. Robert E. Reed-Hill, “The Rotating-Beam Fatigue Test”, Physical
Metallurgy Principles, 3th Edition, 1994, pp.750~752.
11. 陳永增, “金屬模鑄造球墨鑄鐵之信賴度分析”, 國立師範大學工業教育研
究所碩士論文, 台北, 民國80年6月, 第12~15頁。
12. 鍾志賢, “A356鋁合金擠壓鑄件機械性質之可靠度分析”, 國立中央大學機
械工程研究所碩士論文, 桃園, 民國85年6月, 第14~15頁。
13. 劉文勝, “AZ61鎂合金的疲勞性質與破壞分析”, 國立中央大學機械工程研
究所碩士論文, 桃園, 民國89年7月, 第13~15頁。
14. S. K. Tsang, T. S. Lui & L. H. Chen, “ Weibull analysis on the
Elongation Distributions of Austempered Ductile Irons at Various
Tensile Test Temperatures”, 鑄工, 第84期, 第11~18頁。
15. Hiroshi Tamura, Yoshihiro Sugiyama and Taro Kimura, “Estimation of
Fatigue Limit for Ductile Cast Iron”, 日本鑄造工學, 第69卷, 第3
號, 1997, p.234~239.
16. M. Klesnil, P. Lukas, “Sites of Crack Initiation”, Fatigue of Metallic
Materials, Second Revised Edition, 1992, pp.67~70.
17. Robert E. Reed-Hill, “The Microscopic Aspects of Fatigue Failure”,
Physical Metallurgy Principles, 3th Edition, 1994, pp.755~760.
18. Robert E. Reed-Hill, “The Plastic Zone Size Ahead of A Crack”,
Physical Metallurgy Principles, 3th Edition, 1994, pp.792~795.
19. M. Klesnil, P. Lukas, “Kinetics of Crack Growth”, Fatigue of Metallic
Materials, Second Revised Edition, 1992, pp.92~97.
20. C. Laird, “ Fatigue Crack Propagation”, ASTM. STP 415, ASTM,
Philadelphia, 1967, pp.131.
21. W. Weibull, “Statistical Distribution function of Wide
Applicability”, Journal of Apply Mechanics, Sep. 1951, pp.293~297.
22. 可靠度研究小組譯, “實用可靠度”, 和昌出版社, 中壢, 民國73年, 第
245~263頁。
23. Veletsos, Anesitis Stavrou, “Design Approaches”, Chapter 15, 1988,
pp.663~679.
24. Robert E. Reed-Hill, “Dynamic Recovery”, Physical Metallurgy
Principles, 3th Edition, 1994, pp.181~183.
25. Robert E. Reed-Hill, “Polygonization”, Physical Metallurgy
Principles,3th Edition, 1994, pp.233~239.
26. George E. Dieter, “Low-angle Grain Boundaries”, Mechanical
Metallurgy, SI Metric Edition, 1988, pp.193~197.
27. George E. Dieter, “Stacking Faults”, Mechanical Metallurgy, SI Metric
Edition, 1988, pp.135~137.
28. Robert E. Reed-Hill, “Recrystallization”, Physical Metallurgy
Principles, 3th Edition, 1994, pp.240~247.
29. William D. Callister, Jr., “Recovery, Recrystallization and Grain
Growth”, Materials Science and Engineering, 1993, pp.168~173.
30. J. P. Lin, T. C. Lei & X. Y. An, “Dynamic Recrystallization during Hot
Compression in Al-Mg Alloy”, Scripta Metallurgica, Vol. 26, 1992,
pp.1869~1874.
31. K. C. Kapur, L. R. Lamberson, “Reliability in Engineering Design”,
John Wiley & Sons, 1977, pp.291~329.
32. T.S. Srivatsan, S.Anand, D.Veeraghavan, and V.K.Vasudevan, “The
Tensile Response and Fracture Behavior of an Al-Zn-Mg-Cu
Alloy:Influence of Temperature”, Journal of Materials Engineering
and Performance, vol.6(3), June 1977, pp.349~358
33. Patton,G., Rinaldi,C., Brechet,Y., Lormand,G. and Fougeres,R.,
“Study of fatigue damage in 7010 aluminum alloy”, Materials Science
& Engineering A, v A254 n1-2, Oct.15 1998, pp.207~218
34. M.Papakyriacou, H.R.Mayert, S.E.Stanal-Tschegg and M.Groschl,
“Fatigue properties of Al2O3-particle-reinforced 6061 aluminium
alloy in the high-cycle regime”, International Journey of Fatigue,
vol.18 n7, 1996, pp.475~481
35. Teng-Shih Shih, Wen-Sun Liu, Yeong-Jern Chen, “Fatigue of as-extruded
AZ61A magnesium alloy”, Materials Science and Engineering A, 2001
Accepted.
QRCODE
 
 
 
 
 
                                                                                                                                                                                                                                                                                                                                                                                                               
第一頁 上一頁 下一頁 最後一頁 top