本研究將純鈦與6061鋁合金使用摩擦攪拌銲接技術選用偏位與置中兩種接合方法進行異質接合，攪拌棒選用高速鋼，偏位銲接攪拌棒凸銷設計為圓柱形，而置中銲接攪拌棒凸銷設計為半圓球形，傾斜角為2∘，探討不同主軸轉速、進給速度以及攪拌棒形狀對於銲道機械性質之影響，而後對其施以時效與固溶時效處理，比較熱處理前與熱處理後之金相顯微組織、機械性質分析以及元素分布分析。
實驗結果顯示在偏位與置中接合，在主軸轉速1000 rpm、進給速度80 mm/min皆可得到最佳的銲道機械性質，兩種接合方法進行拉伸試驗皆斷在熱影響區，偏位接合最大抗拉強度為158 MPa，而置中接合最大抗拉強度為176 MPa，金相顯微組織可觀察到攪拌區因動態再結晶而有晶粒細化的效果，熱影響區有晶粒粗大化的現象，導致銲件在此區硬度下降。根據EPMA與微硬度分析可觀察到，純鈦與鋁合金在銲道中劇烈攪拌，在兩種材料介面形成金屬間化合物(IMC)，其硬度值最高到達600 HV，與偏位接合相比，置中接合攪拌區純鈦攪動範圍較大，被攪入的鈦碎屑也較多，IMC層厚度也較厚且較為複雜。經由FSW銲後熱處理使用時效處理及固溶時效處理，鋁合金攪拌區及熱影響區晶粒組織有均質化的效果，固溶時效處理可觀察到粗大的晶粒組織會與周圍的組織相結合，形成緊密的組織結構，在微硬度測試可觀察到，鋁合金經由時效處理攪拌區及熱影響區硬度由未進行熱處理的60 HV提升至80 HV；經由固溶時效則可提升100 HV，接近鋁合金母材的硬度，FSW純鈦與鋁合金對接使用固溶時效處理最大抗拉強度可提升至166 MPa。

In this study, the technology of friction stir welding was used to join the dissimilar materials of aluminum alloy 6061 and commercially pure titanium by means of offset joint and center joint. The offset welding stirring rod pin was designed to be cylindrical, while the center welding stirring rod pin was designed to be hemispherical, with an inclination angle of 2˚. The influence of different rotating speeds, travel speeds and shape of stirring rod on the mechanical properties of the weld bead was discussed, and then it was subjected to aging and solution aging treatment, and the metallographic microstructure, mechanical properties, element distribution analysis before and after heat treatment were compared.
The experimental results showed that the best mechanical properties of the weld joint could be obtained at the rotational speed of 1000 rpm and the travel speed of 80 mm/min in the offset joints and center joints. The maximum tensile strength of the offset joint was 158 MPa, and the maximum tensile strength of the center joint was 176 MPa. The metallographic microstructure could observe that the stirring zone has the effect of grain refinement due to dynamic recrystallization, and the heat-affected zone has grains, the phenomenon of coarsening causes the hardness of the weldment to decreased in this area. According to EPMA and microhardness analysis, it could be observed that pure titanium and aluminum alloy were vigorously stirred in the weld bead, and an intermetallic compound (IMC) was formed at the interface of the two materials, and its hardness value was up to 600 HV. The stirring range of pure titanium in the middle-joining stirring zone was larger, and more titanium scraps were stirred, and the thickness of the IMC layer is also thicker and more complicated. Through FSW post-weld heat treatment using aging treatment and solution aging treatment, the grain structure of the aluminum alloy stirring zone and heat affected zone has the effect of homogenization. It could be observed that the coarse grain structure will be combined with the surrounding structure in the solution aging treatment, forming a compact structure. In the microhardness test, it could be observed that the hardness of the aluminum alloy in the stirring zone and heat affected zone is increased from 60 HV without heat treatment to 80 HV after aging treatment, The hardness of the aluminum alloy base metal, the tensile strength of the FSW butt joint could be increase to 166 MPa by solution and aging treatment.

1. W. M. Thomas, E. D. Nicholas, Friction stir welding for the transportation industries, Materials & Design 18. 4-6, 269-273, 1997.
2. M. A. Sutton, B. Yang, A. P. Reynolds, R Taylor, Microstructural studies of friction stir welds in 2024-T3 aluminum. Materials science and engineering: A 323, 1-2, 160-166, 2002.
3. O.T. Inal, A. Szecket, D. J. Vigueras, H. R. Pak, Explosive welding of Ti–6Al–4V to mild‐steel substrates, Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, 3.6, 2605-2609, 1985.
4. M., Fazel-Najafabadi, S. F. Kashani-Bozorg, A. Zarei-Hanzaki. Joining of CP-Ti to 304 stainless steel using friction stir welding technique, Materials & Design 31.10, 4800-4807, 2010.
5. Y. Gao, T. Takuya, N. Kazuhiro, Dissimilar welding of titanium alloys to steels, Transactions of JWRI , 41.2, 7-12. , 2012.
6. S. Zhao, G. Yu, X. He, Y. Zhang, W. Ning, Numerical simulation and experimental investigation of laser overlap welding of Ti6Al4V and 42CrMo, Journal of Materials Processing Technology, 211-3, 530-537, 2011.
7. B. Shanmugarajan, G. Padmanabham, Fusion welding studies using laser on Ti–SS dissimilar combination, Optics and Lasers in Engineering, 50 ,1621–1627, 2012.
8. T. Wang, B. G. Zhang, G. Q. Chen, J. C. Feng, High strength electron beam welded titanium–stainless steel joint with V/Cu based composite filler metals, Vacuum 94, 41–47, 2013.
9. R. K. Shiue, S. K. Wu, J. Y. Shiue, Infrared brazing of Ti–6Al–4V and 17-4 PH stainless steel with (Ni)/Cr barrier layer, Materials Science and Engineering. A 488, 186–194, 2008.
10. H. Dong, L. Yu, D. Deng, W. Zhou, C. Dong, Effect of post-weld heat treatment on properties of friction welded joint between TC4 titanium alloy and 40Cr steel rods, Journal of Materials Science & Technology, 31, 962-968, 2015.
11. E. Atasoy, N. Kahraman, Diffusion bonding of commercially pure titanium to low carbon steel using a silver interlayer, Materials characterization, 59, 1481–1490, 2008.
12. W.B. Lee, S.B. Jung, Effect of microstructure on mechanical properties of friction-welded joints between Ti and AISI 321 stainless steel, Materials transactions, 45, 2805–2811, 2004.
13. R. W. Messler, Principles of welding, Weinheim, Germany: Wiley–VCH Verlag, 1999, 2008.
14. X. Yue, P. He, J. C. Feng, J. H. Zhang, F. Q. Zhu, Microstructure and interfacial reactions of vacuum brazing titanium alloy to stainless steel using an AgCuTi filler metal, Materials characterization, 59, 1721-1727, 2008.
15. P. He, J. Zhang, R. Zhou, X. Li, Diffusion bonding technology of a titanium alloy to a stainless steel web with an Ni interlayer, Materials characterization, 43, 287-292, 1999.
16. B. Zou, H. Zhou, C. Huang, K. Xu, J. Wang, Tool damage and machined-surface quality using hot-pressed sintering Ti (C7N3)/WC/TaC cermet cutting inserts for high-speed turning stainless steels, The International Journal of Advanced Manufacturing Technology, 79, 197-210,2015.
17. 郭承典，”純鈦與 6061 鋁合金摩擦攪拌異質接合之機械性質與抗腐蝕特性研究”，國立臺灣師範大學機電工程學系碩士論文，碩士論文，2019。
18. S. Vaucher, M. Stir, K. Ishizaki, J. M. Catala-Civera, R. Nicula, Reactive synthesis of Ti–Al intermetallics during microwave heating in an E-field maximum, Thermochimica Acta, 522, 151-154, 2011.
19. S. Rajakumar, V. Balasubramanian, Diffusion bonding of titanium and AA 7075 aluminum alloy dissimilar joints—process modeling and optimization using desirability approach, The International Journal of Advanced Manufacturing Technology, 86, 1095-1112, 2016.
20. M. Cheepu, V. Muthupandi, S. Loganathan, Friction welding of titanium to 304 stainless steel with electroplated nickel interlayer, In Materials Science Forum Trans Tech Publications Ltd, 620-625, 2012.
21. N. R. J. Hynes, P. S. Velu, Effect of rotational speed on Ti-6Al-4V-AA 6061 friction welded joints, Journal of manufacturing processes, 32, 288-297, 2018.
22. G. Casalino, M. Mortello, Modeling and experimental analysis of fiber laser offset welding of Al-Ti butt joints, The International Journal of Advanced Manufacturing Technology, 83, 89-98, 2016.
23. J. Y. Lin, S. Nambu, T. Koseki, Interfacial phenomena during ultrasonic welding of ultra-low-carbon steel and pure Ti, Scripta Materialia, 178, 218-222, 2020.
24. H. M. Zhang, Y. J. Chao, Z. Luo, Effect of interlayer on microstructure and mechanical properties of Al–Ti ultrasonic welds, Science and Technology of Welding and Joining, 22, 79-86,2017.
25. H. A. Grebe, H.-R. Pak, M. A. Meyers, Adiabatic shear localization in titanium and Ti-6 pct Al-4 pct V alloy, Metallurgical Transactions A, 16, 761-775, 1985.
26. A. Fuji, In situ observation of interlayer growth during heat treatment of friction weld joint between pure titanium and pure aluminium, Science and technology of welding and joining, 7, 413-416, 2002.
27. L. Zhou, J. Min, W. X. He, Y. X. Huang, X. G. Song, Effect of welding time on microstructure and mechanical properties of Al-Ti ultrasonic spot welds, Journal of Manufacturing Processes, 33, 64-73, 2018.
28. H. M. Zhang, Y. J. Chao, Z. Luo, Effect of interlayer on microstructure and mechanical properties of Al–Ti ultrasonic welds, Science and Technology of Welding and Joining, 22, 79-86, 2017.
29. M. Aonuma, K. Nakata, Effect of calcium on intermetallic compound layer at interface of calcium added magnesium–aluminum alloy and titanium joint by friction stir welding, Materials science and engineering: B, 173, 135-138, 2010.
30. C.Q. Zhang, J.D. Robson, O. Ciuca, P.B. Prangnell, Microstructural characterization and mechanical properties of high power ultrasonic spot welded aluminum alloy AA6111–TiAl6V4 dissimilar joints, Materials Characterization, 97, 83-91, 2014.
31. M. Aonuma, K. Nakata, Dissimilar metal joining of 2024 and 7075 aluminium alloys to titanium alloys by friction stir welding, Materials transactions, 52, 948-952, 2011.
32. H. Bang, H. Bang, H. Song, S. Joo, Joint properties of dissimilar Al6061-T6 aluminum alloy/Ti–6%Al–4%V titanium alloy by gas tungsten arc welding assisted hybrid friction stir welding, Materials & Design, 51, 544-551, 2013.
33. U. Dressler, G. Biallas, U. Alfaro Mercado, Friction stir welding of titanium alloy TiAl6V4 to aluminium alloy AA2024-T3, Materials Science and Engineering: A, 526, 113-117, 2009.
34. N. Bhardwaj, R. G. Narayanan, U. S. Dixit, M. S. J. Hashmi, Recent developments in friction stir welding and resulting industrial practices, Advances in Materials and Processing Technologies, 5-3, 461-496, 2019.
35. K. Takahashi, K. Mori, H. Takebe, Application of titanium and its alloys for automobile parts, In MATEC web of conferences, EDP Sciences.,Vol. 321, 2020.
36. P. L. Threadgill, A. J. Leonard, H. R. Shercliff, P. J. Withers, Friction stir welding of aluminium alloys, International Materials Reviews, 54, 49-93, 2009.
37. W. Zhang, Y. Shen, Y. Yan, R. Guo, Dissimilar friction stir welding of 6061 Al to T2 pure Cu adopting tooth-shaped joint configuration: microstructure and mechanical properties, Materials Science and Engineering: A, 690, 355-364, 2017.
38. A. M. Joseph, C. L. Collins, N. M. Henke, E. E. Yard, S. K. Fields, R. D. Comstock, A multisport epidemiologic comparison of anterior cruciate ligament injuries in high school athletics, Journal of Athletic Training, 48, 810–817, 2013.
39. L. C. Mihata, A. I. Beutler, B. P. Boden, Comparing the incidence of anterior cruciate ligament injury in collegiate lacrosse, soccer, and basketball players: Implications for anterior cruciate ligament mechanism and prevention, American Journal of Sports Medicine, 34, 899–904, 2006.
40. K. D. Shelbourne, T. J. Davis, T. E. Klootwyk, The relationship between intercondylar notch width of the femur and the incidence of anterior cruciate ligament tears: A prospective study, American Journal of Sports Medicine, 26, 402–408, 1998.
41. T. O. Souryal, T. R. Freeman, Intercondylar notch size and anterior cruciate ligament injuries in athletes: A prospective study, American Journal of Sports Medicine, 21, 535–539, 1993.
42. K. D. Shelbourne, T. J. Davis, T. E. Klootwyk, The relationship between intercondylar notch width of the femur and the incidence of anterior cruciate ligament tears: A prospective study, American Journal of Sports Medicine, 26, 402–408, 1998.
43. Jr Brand, C. Jeff, J. Nyland, D. N. Caborn, D. L. Johnson, Soft-tissue interference fixation: Bioabsorbable screw versus metal screw, Arthroscopy, 21, 911–916, 2005.
44. P. Yadav, K. K. Saxena, Effect of heat-treatment on microstructure and mechanical properties of Ti alloys: An overview. Materials Today: Proceedings, 26, 2546-2557, 2020.
45. K. Takahashi, K. Mori, H. Takebe, Application of titanium and its alloys for automobile parts, In MATEC Web of Conferences, EDP Sciences.,Vol. 321, 02003, 2020.
46. 志虹熱處理股份有限公司，鋁合金介紹[online]，Available:
http://www.chihong-ht.com.tw/pdf/ch-k-401.pdf?cv=1
47. G. M. Babekr, Friction Stir Welding (FSW) of Dissimilar Metals and Alloys, 2015.
48. K. Elangovan, V. Balasubramanian, S. Babu, Developing an empirical relationship to predict tensile strength of friction stir welded AA2219 aluminum alloy, Journal of materials engineering and performance, 17, 820-830, 2008.
49. N. Bhardwaj, R. G. Narayanan, U. S. Dixit, M. S. J. Hashmi, Recent developments in friction stir welding and resulting industrial practices, Advances in Materials and Processing Technologies, 5-3, 461-496, 2019.
50. W. J. Arbegast, Hot deformation of aluminum alloys III, Warrendale (PA): TMS, 2003.
51. S. M. Chowdhury, D. L. Chen, S. D. Bhole, X. Cao, Tensile properties of a friction stir welded magnesium alloy: Effect of pin tool thread orientation and weld pitch, Materials Science and Engineering: A, 527, 21-22, 6064-6075, 2010.
52. T. DebRoy, H. Bhadeshia, K. D. H., Friction stir welding of dissimilar alloys–a perspective, Science and Technology of Welding and Joining, 15-4, 266-270, 2010.
53. N. T.Kumbhar, K. Bhanumurthy, Friction stir welding of Al 5052 with Al 6061 alloys, Journal of metallurgy, 2012, 2012.
54. P. L. Threadgill, Terminology in friction stir welding, Science and Technology of Welding and Joining, 12, 357-360, 2007.
55. M. Aonuma, K. Nakata, Dissimilar metal joining of ZK60 magnesium alloy and titanium by friction stir welding, Materials Science and Engineering: B, 177-7, 543-548, 2012.
56. J. W. Choi, H. Liu, H. Fujii, Dissimilar friction stir welding of pure Ti and pure Al. Materials Science and Engineering: A, 730, 168-176, 2018.
57. R. S. Mishra, Z. Y. Ma, Friction stir welding and processing, Materials science and engineering: R: reports, 50, 1-78, 2005.
58. C. Rowe, T. Wayne, Advances in tooling materials for friction stir welding, Technical report. Internet publication by TWI 13th January, 2005.
59. H. Fujii, L. Cui, M. Maeda, K. Nogi, Effect of tool shape on mechanical properties and microstructure of friction stir welded aluminum alloys, Materials Science and Engineering: A, 419, 25-31, 2006.
60. K. Ishida, Y. Gao, K. Nagatsuka, M. Takahashi, K. Nakata, Microstructures and mechanical properties of friction stir welded lap joints of commercially pure titanium and 304 stainless steel, Journal of Alloys and Compounds, 630, 172-177, 2015.
61. 康宗瑋，”鋁合金之摩擦攪拌銲接之實驗”，國立中山大學機械與機電工程研究所碩士論文，碩士論文，2008。
62. R. R. Ambriz, G. Barrera, R. García, V. H. López, The microstructure and mechanical strength of Al-6061-T6 GMA welds obtained with the modified indirect electric arc joint, Materials & Design, 31, 2978−2986, 2010.
63. M. N. Gussev, N. Sridharan, M. Norfolk, K. A. Terrani, S. S. Babu, Effect of post weld heat treatment on the 6061 aluminum alloy produced by ultrasonic additive manufacturing, Materials Science and Engineering: A, 684, 606-616, 2017.
64. D. Bandyopadhyay, R. C. Sharma, N. Chakraborti, The Ti-Al-C system, Journal of phase equilibria, 21, 195-198. 2000.