本實驗利用摩擦攪拌製程技術對Cu-40%Zn進行加工，利用其大量塑性變形以及熱加工的特性能有效的製造均勻的細晶結構，而利用不同的熱處理條件能製造出不同比例的雙相結構，接續以不同製程參數的摩擦攪拌製程進行加工，並以光學顯微鏡(Optical Microscope, OM)、穿透式電子顯微鏡(Transmission Electron Microscopy, TEM)與背向散射電子繞射(Electron Back Scattered Diffraction, EBSD)分析材料的微結構，以微克氏微硬度(Vickers microhardness)與拉伸實驗來分析機械性質的變化。
Cu-40%Zn經不同熱處理情況，發現在700℃下持溫一小時後水淬至室溫能製造出大量的雙相結構並且降低其內應力，摩擦攪拌後其晶粒大小明顯細化，約分佈在1~6μm，且微結構由原本的雙相結構變成幾乎單相結構分佈。
調控不同摩擦攪拌製程參數觀察到隨轉速降低、走速上升以及道次增加晶粒細化的效果提升，其中晶粒細化效果最好的參數為走過四道次摩擦攪拌製程的情況因此含有最高的強度，得知以不同道次的條件對於材料微結構與機械性質影響比較大。
本實驗同時以不同的冷卻媒介來調控經摩擦攪拌後材料的冷卻速率，發現冷卻速率快的條件下再結晶比例、高角度晶界、雙晶晶界比例較少，但可減少晶粒成長的現象。

In this work, fine-grained Cu-40%Zn brass was produced by friction stir processing (FSP). The severe plastic deformation (SPD) and hot deformation provided by FSP could effectively refine the grains. By using proper heat treatment, two different proportions of α/β dual-phase structure were produced, which were subsequently processed by different FSP parameters to form fine-grained structure. The effect of FSP parameters on the microstructure and mechanical properties was studied. The microstructure was characterized by using transmission electron microscopy (TEM) and electron backscattered diffraction (EBSD), and both microhardness and tensile test were used to measure the mechanical properties.
A dual-phase structure with 30% β-phase was obtained by annealing the alloy at 700oC for 1 hour and water quenching to room temperature. After FSP, the alloy contains nearly complete α-phase in all processing conditions, in which the grain size ranges from 1~6 μm. The grain size decreases as the tool rotation rate decreases or the tool transverse speed increases. An increase in FSP pass is the most effective way to refine the grain size and results in high strength. The study also indicates that a faster cooling rate in FSP could results in smaller grains by limiting grain growth.

論文審定書 i
致謝 ii
摘要 iii
Abstract iv
目錄 v
表目錄 vii
圖目錄 viii
第一章 前言 1
第二章 文獻回顧 2
2.1 銅鋅金屬 2
2.1.1 α與β相 2
2.1.2 雙晶 2
2.1.3改進銅鋅金屬的機械性質 3
2.2超細晶的研究 4
2.2.1超細晶金屬強度 4
2.2.2 細晶延展性 5
2.2.3降伏現象與路得氏變形(Lüders band) 5
2.3 摩擦攪拌製程 6
2.3.1 摩擦攪拌銲接 6
2.3.2 摩擦攪拌製程參數 7
2.3.3經FSP後材料流動的情形 8
2.3.4 攪拌區溫度分布 10
2.3.5 殘餘應力(Residual stress) 11
2.3.6 再結晶 12
2.4 Cu-40%Zn經FSW後的結果 13
第三章 實驗製程 14
3.1材料 14
3.2熱處理 14
3.3摩擦攪拌製程 14
3.3 微結構分析 15
3.3.1 X光分析相組成 15
3.3.2 光學顯微鏡(OM) 15
3.3.3 掃描試電子顯微鏡 (SEM) 15
3.3.4背向散射電子繞射分析法 (EBSD) 15
3.3.5 穿透式電子顯微鏡 (TEM) 16
3.4微硬度分析 16
3.5拉伸試驗 17
3.6 試片命名 17
第四章 實驗結果 18
4.1 微結構分析 18
4.1.1 熱處理 18
4.1.2 摩擦攪拌製程 19
4.1.3 FSP微結構觀察 19
4.1.4 轉速 20
4.1.5 走速 20
4.1.6冷卻媒介 21
4.1.7 道次 21
4.1.8 極圖(Pole figure) 22
4.2機械性質分析 22
4.2.1熱處理 22
4.2.2 轉速 23
4.2.3走速 24
4.2.4 冷卻媒介 24
4.2.5 道次 24
第五章 討論 26
5.1 熱處理 26
5.2 摩擦攪拌製程參數的影響 26
5.2.1轉速 26
5.2.2走速 26
5.2.3 道次 27
5.3 調控冷卻媒介對微結構的影響 27
5.4 摩擦攪拌製程與相組成的關係 28
5.5 強化機構 28
第六章 結論 30
第七章 參考文獻 31
表 34
圖 37

1. E. W. Qin, L. Lu, N. R. Tao, J. Tan, K. Lu. Enhanced fracture toughness and strength in bulk nanocrystalline Cu with nanoscale twin bundles. Acta Mater. 57 (2009) 6215-25.
2. W. F. Smith. Structure and properties of engineering alloys. McGraw-Hill Press. (1993)
3. Y. H. Zhao, X. Z. Liao, Z. Horita, T. G. Langdon, Y. T. Zhu. Determining the optimal stacking fault energy for achieving high ductility in ultrafine-grained Cu-Zn alloys. Mater. Sci. Eng. A 493 (2008) 123-9.
4. R. H. Reed-Hill, R. Abbaschian. Physical Metallurgy Principles. PWS-Kent Publishing Company. Boston. (1994)
5. S. Mahajan, C. S. Pande, M. A. Imam, B. B. Rath. Formation of annealing twins in FCC crystals. Acta Mater. 45 (1997) 2633-38.
6. Y. Jin, M. Bernacki, G. S. Rohrer, A. D. Rollett, B. Lin, N. Bozzolo. Formation of annealing twins during recrystallization and grain growth in 304L austenitic stainless steel. Mater. Sci. Forum 753 (2013) 113-6.
7. F. Ebrahimi, Z. Ahmed, H. Li. Effect of stacking fault energy on plastic deformation of nanocrystalline face-centered cubic metals. Appl. Phys. Lett. 85 (2004) 3749-51.
8. K. Neishi, Z. Horita, T. G. Langdon. Achieving superplasticity in a Cu-40%Zn alloy through severe plastic deformation. Scr. Mater. 45 (2001) 965-70
9. T. G. Neih, J. Wadswoth, O. D. Sherby. Superplasticity in metals and ceramics. Cambridge. Cambridge University Press. (1997)
10. T. Chandra, J. J. Jonas, D. M. R. Taplin. Grain-boundary sliding and intergranular cavitation during superplastic deformation of α/β brass. J. Mater. Sci. 13 (1978) 2380-4.
11. J. W. D. Patterson, N. Ridley. Effect of phase proportions on deformation and cavitation of superplastic α/β brass. J. Mater. Sci. 16 (1981) 457-64.
12. A. W. Anthony. Yielding in nickel as a function of grain or cell size. Acta Mater. 23 (1975) 1337-42.
13. 庾忠義，超細晶鋁之機械性質，中山大學博士論文 (2003)。
14. R. A. Masumura, P. M. Hazzledine, C. S. Pandel. Yield stress of fine grained materials. Acta Mater. 46 (1998) 4527-34.
15. K. Surekha, A. Els-Botes. Development of high strength, high conductivity copper by friction stir processing. Mater. Design 32 (2011) 911-6.
16. W. B. Morrison, R. L. Miller. The ductility of ultrafine grain alloys. Ultrafine-grain Metals. Syracuse University Press. (1970) pp.183-211.
17. D. Hull, D. J. Bacon. Introduction to dislocations Butterworth Heinemann Press. (2001)
18. W. M. Thomas, E. D. Nicholas, J. C. Needham, M. G. Murch, P. Templesmith, C. J. Dawes. GB Patent Application. No. 9125978.8; Dec 1991.
19. R. S. Mishra, Z. Y. Ma. Friction stir welding and processing. Mater. Sci. Eng. R 50 (2005) 1-78.
20. Z. Y. Ma. Friction stir processing technology: A review. Metall. Mater. Trans. A 39 (2008) 642-58.
21. 蔡馥郁，摩擦攪拌製程對AC8A鋁矽合金微結構及機械性質的影響，國立中山大學碩士論文 (2008)。
22. M. Guerra, J. C. McClure, L. E. Murr, A. C. Nunes, M. W. Mahoney, R. S. Mishra, S. L. Semiatin, D. P. Filed. Friction stir welding and processing, TMS, Warrendale, PA, USA, (2001) p. 25.
23. K. N. Krishnan. On the formation of onion rings in friction stir welds. Mater. Sci. Eng. A 327 (2002) 246-51.
24. Z. Y. Ma, S. R. Sharma, R. S. Mishra, M. W. Mahoney. Microstructural modification of cast aluminum alloys via friction stir processing. Mater. Sci. Forum 426-432 (2003) 2891-6.
25. Z. Y. Ma, S. C. Tjong, L. Geng. In-situ Ti-TiB metal-matrix composite prepared by a reactive pressing process. Scr. Mater. 42 (2000) 367-73.
26. Z. Y. Ma, S. C. Tjong, L. Geng, Z. G. Wang. Effect of interfacial reaction on tensile and creep behaviors of aluminum-borate-whisker-reinforced AA6061 composite. J. Mater. Res. 15 (2000) 2714-29.
27. A.P. Reynolds, Visualisation of material flow in autogenous friction stir welds. Sci. Technol. Weld. Joi. 5 (2000) 120-4.
28. M. W. Mahoney, C. G. Rhodes, J. G. Flintoff, R. A. Spurling, W. H. Bingel. Properties of friction-stir-welded 7075 T651 aluminum. Metall. Mater. Trans. A 29 (1998) 1955-64.
29. W. Tang, X. Guo, J. C. McClure, L. E. Murr, A. Nunes. Heat Input and Temperature Distribution in Friction Stir Welding. J. Mater. Process. Manuf. Sci. 7 (1998) 163-72.
30. 張志溢，摩擦旋轉攪拌製程對AZ31鎂合金晶粒細化之研究，國立中山大學碩士論文 (2004)。
31. H. W. Park, T. Kimura, T. Murakami, Y. Naganod, K. Nakata, M. Ushio. Microstructures and mechanical properties of friction stir welds of 60% Cu-40% Zn copper alloy. Mater. Sci. Eng. A 371 (2004) 160-9.
32. M. Abbasi Gharacheh, A. H. Kokabi, G. H. Daneshi, B. Shalchi, R. Sarrafi. The influence of the ratio of rotational speed/traverse speed (ω/v) on mechanical properties of AZ31 friction stir welds. Int. J. Mach. Tools Manuf. 46 (2006) 1983-87.
33. V. Balasubramanian. Relationship between base metal properties and friction stir welding process parameters. Mater. Sci. Eng. A 480 (2008) 397-403.
34. J. Q. Su, T. W. Nelson, C. J. Strling. Grain refinement of aluminum alloys by friction stir processing. Philos. Mag. 86 (2006) 1-24.
35. K. Savolainen. Friction stir welding of copper and microstructure and properties of the welds. Department of Engineering Design and Production, Aalto University. Doctoral dissertation. (2012)
36. G. M. Xie, Z. Y. Ma, L. Geng. Partial recrystallization in the nugget zone of friction stir welded dual-phase Cu–Zn alloy. Philos. Mag. 89 (2009) 1505-16.
37. G. M. Xie, Z. Y. Ma, L. Geng. Effects of friction stir welding parameters on microstructures and mechanical properties of brass Joints. Mater. Trans. 49 (2008) 1698-701.
38. G. R. Canova, U. F. Kocks, J. J. Jonas. Theory of torsion texture development. Acta Mater. 32 (1984) 211-26.
39. J. R. Davis. Copper and copper alloys. ASM International (2001).
40. M. A. Meyers, K. K. Chawla. Mechanical behavior of materials. Cambridge: Cambridge University Press. (2009)