本研究藉由粉末冶金方式混合鋁-銅，鋁-鈦以及鋁-矽三種元素粉，接著利用摩擦攪拌製程 (fricion stir processing, FSP) 製備出具有超細晶結構的顆粒強化鋁基複材 (particle-reinforced aluminum matrix composites)。論文主要探討此三種雙相複材微結構的形成機制及其與機械性質之關係，此外亦一併探討這些雙相複材之強化機制。
在鋁-矽系統中，使用多道次摩擦攪拌製程將矽的顆粒打碎並均勻分散在鋁母材中。經由4道次摩擦攪拌製程後，鋁及矽晶粒皆可由40微米快速細化至2微米以下，含大量二次相之鋁-矽複材展現高強度並具優異之延展性。
在鋁-鈦與鋁-銅兩系統，藉由摩擦攪拌製程之摩擦生熱及熱加工，促使鋁與鈦以及鋁與銅粉末之間的原位反應(in-situ reaction)起始進行，分別產生大量的Al3Ti與Al2Cu奈米級介金屬化合物顆粒。摩擦攪拌製程在此提供了下述功能：(1) 劇烈塑性變形使得材料混合及細化；(2) 足夠溫度促使原位反應發生進而生成介金屬化合物；(3) 使材料完全緻密化的熱固製程。
在Al-Al3Ti 複材中，大量的奈米級Al3Ti介金屬化合物顆粒均勻地分散在次微米晶粒的鋁母材中。根據此微結構所對應複材的高強度特性，推測其主要的強度貢獻是來自於細小鋁晶粒以及大量Al3Ti顆粒散佈在母材中所造成之Orowan強化效應。經由摩擦攪拌製程後的Al-Al2Cu及鋁-矽兩種雙相複材，由於具有較粗大二次相顆粒及鋁晶粒，導致降伏强度低於Al-Al3Ti 雙相複材。
以上三種複材之楊氏模數皆隨著強化相顆粒的增加而增加，並且皆符合Halpin-Tsai經驗式之預測。另外此三種複材的壓縮降伏強度皆高於拉伸降伏強度，由實驗結果應是鋁母材中之拉伸殘餘應力所致。由於複材中的強化相顆粒與鋁母材之熱膨脹係數不同，所以在摩擦攪拌製程的冷卻過程中會產生殘餘應力。

Friction stir processing (FSP) is applied to produce particulate-reinforced aluminum matrix composites with ultrafine grained structure from elemental powder mixtures of Al-Cu, Al-Ti and Al-Si. The microstructures of the composites were characterized by the use of XRD, SEM and TEM. Microhardness, tensile and compressive tests were performed to evaluate the mechanical properties of these composites. The mechanisms of microstructure evolution in FSP and the strengthening mechanisms in these composites are discussed.
In the Al-Si system, the Si particles were broken and uniformly distributed in the stir zone by the application of multiples-pass FSP. The average size of Si particles and Al grains were refined to below ~2

Table of Contents I
List of Tables IV
List of Figures VI
Abstract XIV
中文摘要 XVI
Acknowledge XVII
Chapter 1 Introduction 1
Chapter 2 Literatures Review 4
2.1 Friction stir welding (FSW) & friction stir processing (FSP) 4
2.1.1 Introduction of FSW/FSP 4
2.1.2 Advantages and applications of FSW/FSP 4
2.1.3 Metal flow in FSW/FSP 6
2.1.4 Temperature distribution in FSW/FSP 8
2.1.5 Microstructure evolution 8
2.1.6 Grain refinement in the stirred zone 10
2.1.7 Mechanical properties 11
2.2 Metal matrix composites (MMCs) 14
2.2.1 Elastic modulus of particulate reinforced MMCs 15
2.2.2 Strengthening mechanisms of particulate reinforced MMCs 16
2.2.3 In-situ particulate-reinforced MMCs 19
2.2.4 Intermetallic-reinforced Al-matrix in-situ composites 21
Chapter 3 Experimental Procedures 24
3.1 Materials 24
3.2 Fabrication of billets for friction stir processing 24
3.2.1 Powder mixing 24
3.2.2 Cold compaction 24
3.2.3 Sintering 25
3.3 Friction stir processing (FSP) 25
3.4 Microstructure analysis 26
3.4.1 Microscopic observation 26
3.4.2 X-ray diffraction (XRD) 26
3.4.3 Differential thermal analysis (DTA) 27
3.4.4 Transmission electron microscopy (TEM) 27
3.5 Mechanical properties 28
3.5.1 Microhardness measurement 28
3.5.2 Tensile and compressive tests 28
Chapter 4 Results 29
4.1 Al-Si alloys 29
4.1.1 Microstructure of specimens produced by FSP 29
4.1.2 Mechanical properties 31
4.2 Al-Cu alloys 32
4.2.1 Influence of sintering temperature on the sintered microstructure 33
4.2.2 Influence of sintering temperature on the microstructure produced by FSP 34
4.2.3 Effect of Cu-content of the microstructure and properties produced
by FSP 35
4.2.4 Mechanical properties 38
4.3 Al-Ti alloys 39
4.3.1 Al-Ti reaction during sintering 39
4.3.2 Al-Ti reaction during FSP 40
4.3.3 Microstructure of Al-Al3Ti nanocomposites observed by TEM 41
4.3.4 Mechanical properties 42
Chapter 5 Discussion 44
5.1 In-situ reaction and microstructure development in FSP 44
5.1.1 Al-Ti system 44
5.1.2 Al-Cu system 45
5.2 Mechanical properties 46
5.2.1 Young’s modulus of Al-Si, Al-Al2Cu and Al-Al3Ti composites 47
5.2.2 Residual stresses in the composites produced by FSP 47
5.2.3 Strengthening mechanisms 50
5.2.4 Comparison of the mechanical properties 54
Chapter 6 Conclusion 57
Chapter 7 References 129
Appendix A 139

Aravind M, Yu P, Yau MY and Ng DHL. “Formation of Al2Cu and AlCu intermetallics in Al(Cu) alloy matrix composites by reaction sintering” Mater Sci Eng A 380A (2004), p384.
Arbegast WJ. In: Jin Z et al., editors. “Modeling friction stir joining as a metalworking process” Hot Deformation of Aluminum Alloys III. Warrendale, PA: TMS (2003), p313.
Barlow IC, Jones H and Rainforth WM. “Evolution of microstructure and hardening and the role of Al3Ti coarsening, during extended thermal therament in mechanically alloyed Al-Ti-O based materials” Acta Mater 49 (2001), p1209.
Benavides S, Li Y, Murr LE, Brown D and McClure JC. “Low-temperature friction-stir welding of 2024 aluminum” Scripta Mater 41 (1999), p809.
Berbon PB, Bingel WH, Mishra RS, Bampton CC and Manohey MW. “Friction stir processing: a tool to homogenize nanocomposite aluminum alloys“ Scripta Mater 44 (2001), p61.
Chang CI, Lee CJ and Huang JC. “Relationship between grain size and Zener-Holloman parameter during friction stir processing in AZ31 Mg alloys” Scripta Mater 51 (2004), p5091.
Charit I and Mishra RS. “High strain rate superplasticity in a commercial 2024 Al alloy via friction stir processing” Mater Sci Eng A 359A (2003), p290.
Charit I, Mishra RS, Manohey MW. “Multi-sheet structures in 7475 aluminum by friction stir welding in concert with post-weld superplastic forming” Scripta Mater 47 (2002), p631.
Cheng YC, Wang SH, Kao PW, Chang CP. “Microstructures and mechanical properties of mechanically alloyed Al-Al3Ti alloys” Mater Sci Forum 217 (1996), p1891.
Cheng Y C (鄭永權) ”以機械合金法製備之Al-Al3Ti 合金在不同應變速率下之變形行為” 國立中山大學碩士論文(1985).
Choi Y, Mullins ME, Wijayatilleke K, Lee JK. “Fabrication of metal matrix composites of TiC-Al through self-propagating synthesis reaction” Metall Mater Trans A 23A (1992), p2387.
Clyne TW, Withers PJ “An Introduction to Metal Matrix Composites” Cambridge, Cambridge University Press, (1993).
Colligan K. “Material flow behavior during friction stir welding of aluminum” Weld J 78 (1999), p229-s.
Das SK and Davis LA. ”High performance aerospace alloys via rapid solidification processing” Mater Sci Eng 98 (1988), p1.
Dunand DC and Mortensen A. “Reinforced silver chloride as a model material for the study of dislocations in metal matrix composites” Mater Sci Eng A 144A (1991), p179.
Feng CF and Froyen L. “In-situ P/M Al/(ZrB2+Al2O3) MMCs: Processing, microstructure and mechanical characterization” Acta Mater 47 (1999), p4571.
Gale WF, Totemeier TC and Smithells CJ. “Smithells Metals Reference Book, 8th ed.” Elsevier;2004.
Genevois C, Deschamps A, Denquin A, Doisneau-cottignies B. “Quantitative investigation of precipitation and mechanical behaviour for AA2024 friction stir welds” Acta Mater 53 (2005), p2447.
Gotman I, Koczak MJ and Shtessel E. “Fabrication of Al matrix in situ composites via self-propapatiomg synthesis” Mater Sci Eng A 187A (1994), p189.
Heurtier P, Desrayaud C and Montheillet F. ”A thermomechanical analysis of the friction stir welding process” Mater Sci Forum 396-402 (2002), p1537.
Hull D. An introduction to composite materials. New York: Cambridge University Press, (1981).
Hull D, Clyne TW. An Introduction to Composite Materials. 2nd ed. Cambridge University Press, (1996), p66.
Jata KV and Semiatin SL. “Continuous dynamic recrystallization during friction stir welding of high strength aluminum alloys” Scripta Mater 43 (2000), p743.
Jata KV, Sankaran KK and Ruschau JJ. “Friction stir welding effects on microstructure and Fatigue of aluminum alloy 7050-T7451” Metall Mater Trans A 31A (2000), p2181.
Kendig KL, and Miracle DB. “Strengthening mechanisms of an Al-Mg-Sc-Zr alloy” Acta Metall 50 (2002), p4165
Kevorkijan VM. ”Aluminum composites for automotive application: a global perspective JOM 51 (1999), p54.
Köster U, Liu W Liebertz H and Michel M. “Mechanical properties of quasicrystalline and crystalline phase in Al-Cu-Fe alloys” J of Non-Crystalline Solids 153&154 (1993), p446.
Krishnan KN. “On the formation of onion rings in friction stir welds” Mater Sci and Eng A 327A (2002), p246.
Kwon YJ, Shigematsu I and Saito N. “Mechanical properties of fine-grained aluminum alloy produced by friction stir process” Scripta Mater 49 (2003), p785.
Kwon YJ, Saito N and Shigematsu I. “Friction stir process as a new manufacturing technique of ultrafine grained aluminum alloy” J Mater Sci Lett 21 (2002), p 1473.
Kuruvilla AK, Prasad KS, Bhanuprasad VV, and Mahajan YR. ” Microstructure-property correlation in Al/TiB2 (XD) composites” Scripta Metall Mater 24 (1990), p873.
Lawson WHS, and Kerr HW. “Mechanical behavior of rapidly solidified Al-Al2Cu and Al-Al3Ni composites” Metall Mater Trans A 2A (1971), p2853.
Lee WB, Yeon YM and Jung SB. ”The improvement of mechanical properties of friction-stir-welded A356 Al alloy” Mater Sci and Eng A 355A (2003), p154.
Lerf R, Morris DG.. “Mechanical alloying of Al-Ti alloys” Mater Sci and Eng A 128A (1990), p119.
Li Y, Trillo EA, Murr LE. ”Friction stir welding of aluminum alloy 2024 to silver” J Mater Sci Lett 19 (2000), p1047.
Liu G, Murr LE, Niou C-S, McClure JC and Vega FR. “Microstructural aspects of the friction-stir welding of 6061-T6 aluminum” Scripta Mater 37 (1997), p355.
Liu HJ, Fujii H, Maeda M and Nogi K. “Tensile properties and fracture locations of friction stir welded joints of 2017-T351 aluminum” J Mater Process Tech 142 (2003), p692.
Lloyd DJ. ”Particle reinforced aluminum and magnesium matrix composites” Inter Mater Rev 39 (1994), p1.
Ma ZY, Mishra RS and Manohey MW. “Superplastic deformation behaviour of friction stir processed 7075Al alloy” Acta Mater 50 (2002), p4419.
Ma ZY and Mishra RS. ”Cavitation in superplastic 7075Al alloys prepared via friction stir processing” Acta Mater 51 (2003), p3551.
Ma ZY, Mishra RS and Mahoney MW. “Superplasticity in cast A356 induced via friction stir processing” Scripta Mater 50 (2004), p931.
Ma ZY, Li JH, Li SX, Ning XG, Lu YX and Bi J. “Property-microstructure correlation in in situ formed Al2O3, TiB2 and Al3Ti mixture-reinforced aluminium” J Mater Sci 31 (1996), p741.
Ma ZY and Tjong SC. “In situ ceramic particle-reinforced aluminum matrix composites fabricated by reaction pressing in the TiO2(Ti)-Al-B(B2O3) system” Metall Mater Trans A 28A (1997), p1931.
Ma ZY, Mishra RS and Manohey MW. “Friction stir processing for microstructural modification of an aluminum casting” Friction Stir Welding and Processing II, TMS, (2003), p221.
Ma ZY, Sharma SR and Mishra RS. ” Effect of multiple-pass friction stir processing on microstructure and tensile properties of a cast aluminum-silicon alloy” Scripta Mater 54 (2006), p1623.
Mahoney MW, Rhodes CG, Flintoff JG, Spurling RA and Bingel WH. “Properties of fiction stir welded 7075 T651 aluminum” Metall Mater Trans A 29A (1998), p1955.
Martin JW. Micromechanisms in particles-hardened alloys. New York: Cambridge University Press, (1980).
Miles MP, Mahoney MW, Nelson TW and Mishra RS. “Finite element simulation of plane strain thick plate bending of friction stir processed 2519 aluminum” Friction Stir Welding and Processing II, TMS, (2003), p253.
Miller WS, Humphreys FJ. “Strengthening mechanisms in particulate metal matrix composites” Scripta Met Mter 25 (1991), p33.
Mirchandani PK, Benn RC, Heck KA. In: Lee WE et al., editors. “Light-Weight Alloys for Aerospace Applications” Warrendale, PA: TMS, (1989), p33.
Mishra RS, Ma ZY and Charit I. “Friction stir processing: a novel technique for fabrication of surface composite” Mater Sci Eng A 341A (2003), p307.
Mishra RS, Ma ZY. “Friction stir welding and processing” Mater Sci Eng R 50 (2005), p1.
Mishra RS, Mahoney MW, McFadden SX, Mara NA and Mukherjee AK. “High strain rate superplasticity in a friction stir processed 7075 Al alloy” Scripta Mater 42 (2000), p163.
Mishra RS. “Friction stir processing technologies” Adv Mater Process 161 (2003), p43.
Murakami Y. Structure and properties of nonferrous alloys (Aluminum-Based Alloys). Materials Science and Technology 8 (1996), p215.
Nardone VC and Prewo KM. “On the strength of discontinuous silicon carbide reinforced aluminum composites” Scripta Metall 20 (1986), p43.
Nakamura M and Kimura K. ”Elastic constants of TiAl3 and ZrAl3 single crystals” J Mater Sci 26 (1991), p2208.
Pan J, Li JH, Fukunaka H, Ning XG, Ye HQ, Yao ZK, Yang M. “Microstructural study of the interface reaction between titania whiskers and aluminum” Composites Sci Technol 57 (1997), p319.
Park SHC, Sato YS, Kokawa H. “Basal plane texture and flow pattern in friction stir weld of a magnesium alloy” Metall Mater Trans A 34A (2003), p987.
Peel M, Steuwer A, Preuss M, Withers PJ. “Microstructure, mechanical properties and residual stresses as a function of welding speed in aluminum AA5083 friction stir welds” Acta Mater 51 (2003), p4791.
Ramakrishnan N. “An analytical study on strengthening of particulate reinforced metal matrix composites” Acta Mater 44 (1996), p69.
Reynolds AP. “Visualisation of material flow in autogenous fraction stir welds” Sci. Technol. Weld. Joing 5 (2000), p120.
Rhodes CG., Mahoney MW, Bingel WH and Calabrese M. ”Fine-grain evolution in friction-stir processed 7050 aluminum” Scripta Mater 48 (2003), p1451.
Rhodes CG., Mahoney MW, Bingel WH, Spurling RA and Bapoton CC. “Effects of friction stir welding on microstructure of 7075 aluminum” Scripta Mater 36 (1997), p69.
Roebuck R, Gorley TAE and McCartney LN. “Mechanical property test procedures for metal matrix composites” Mater Sci Tech 5 (1989), p105.
Santella ML, Engstrom T, Storjohann D and Pan TY. ”Effects of friction stir processing on mechanical properties of the cast aluminum alloys A319 and A356” Scripta Mater 53 (2005), p201.
Sato YS, Kokawa H, Enomoto M and Jogan S. “Microstructurral evolution of 6063 aluminum during friction-stir welding” Metall Mater Trans A, 30A (1999), p2429.
Sato YS, Kokawa H, Ikeda K, Enomoto M, Jogan S and Hanshimoto T. “Microtexture in the friction-stir weld of an aluminum alloy” Metall Mater Trans A 32A (2001a), p941.
Sato YS, Park SHC and Kokawa H. “Distribution of tensile property and microstructure in friction stir weld of 6063 aluminum” Metall Mater Trans A 32A (2001b), p3023.
Seidel TU and Reynolds AP. “Visualization of the Material flow in AA2195 friction stie welds using a marker insert technique” Metall Mater Trans A 32A (2001), p2879.
Senkov ON, Froes FH, Stolyarov VV, Valiev RZ, Liu J. “Microstructure and microhardness of an Al-Fe alloy subjected to severe plastic deformation and aging” Nanostruct Mater 10 (1998), p691.
Sharma SR, Ma ZY, Mishra RS. “Effect of friction stir processing on fatigue behavior of A356 alloy” Scripta Mater 51 (2004), p237.
Srinivasan S, Chen SR, Schwarz RB. “Synthesis of Al/Al3Ti two alloys by mechanical alloying” Mater Sci and Eng A 153A (1992), p691.
Su JQ, Nelson, TW and Sterling CJ. “Friction stir processing of large-area bulk UFG aluminum alloys” Scripta Mater 52 (2005), p135.
Su JQ, Nelson TW, Mishra RS, Manohey MW. “Microstructural investigation of friction stir welded 7050-T651 aluminium” Acta Mater 51 2003, p713.
Sutton MA, Yang B, Reynolds AP and Taylor R. “Microstructural studied of friction stir welds in 2024-T3 aluminum” Mater Sci and Eng A 323A (2002), p160.
Thomas WM, Nicoholas ED, Needham JC, Church MG, Templesmith P and Dawes CJ. “Friction Stir Butt Welding”, G.B. Patent Application No. 9125978.8, December 1991; US Patent No. 5460317, October 1995.
Tjong SC and Ma ZY. “Microstructural and mechanical characteristic of in situ metal matrix composites” Mater Sci Eng R 29 (2000), p49.
Tjong SC, Lau KC and Wu SQ. “Wear of Al-based hybrid composites containing BN and SiC particulates” Metall Mater Trans A 30A (1999), p2551.
Tong XC, Fang HS. “Al-TiC composites in situ processed by ingot metallurgy and rapid solidification technology: part II . mechanical behavior” Metall Mater Trans A 29A (1998), p893.
Vaidya RU and Chawla KK. “Thermal Expansion of Metal-Matrix Composites” Compos Sci Technol 50 (1994), p13.
Varin RA. “Intermwtallic reinforced light-metal matrix in-situ composites” Metall Mater Trans A 33A (2002), p193.
Vyletel GM, Allison JE, Aken DCV. “Recrystallization and grain growth phenomena in a particle-reinforced aluminum composite” Metall Mater Trans A 26A (1995), p1395.
Wang SH, Kao PW. “The strengthening effect of Al3Ti in high temperature deformation of Al-Al3Ti composites”Acta Mater 46 (1998), p2675.
Wang SH, Kao PW, Chang CP. ”The strengthening effect of Al3Ti in ultrafine grained Al-Al3Ti alloys” Scripta Mater 40 (1999), p289.
Westwood ARC, Winzer SR, in Psaras PA, Langford HD(Eds.), Advanced Materials Research, National Academy Press, Washungton, DC, (1987), p225.
Wu JM, Zheng SL, Li ZZ. “Thermal stability and its effects on the mechanical properties of rapidly solidified Al-Ti alloys” Mater Sci Eng A 289A (2000), p246.
Xu S, Deng X, Reynolds, AP and Seidel TU. “Finite element simulation of material flow in friction stir welding” Science and Technology of Welding and Joining 6 (2001), p191.
Yamaguchi M, Umakoshi Y and Yamane T. “Plastic deformation of the intermetallic compound Al3Ti ” Phil Mag A 48 (1987), p301.
Yu CY, Kao PW, Chang CP. “Transition of tensile deformation behaviors in ultrafine-grained aluminum” Acta Mater 53 (2005), p4019.
Yu P, Deng CJ, Ma NaG, Yau MY and Ng DHL. “Formation of nanostructured eutectic network in α-Al2O3 reinforced Al–Cu alloy matrix composite” Acta Mater 51 (2003), p3445.
Zhang HW, Zhang Z, Chen JT. “The finite element simulation of the friction stir welding process “ Mater Sci Eng A 403A (2005), p340.
Zhang Z and Chen DL. “Consideration of Orowan strengthening effect in particulate-reinforced metal matrix nanocomposite: A model for predicting their yield strength” Scripta Mater 4 (2006), p1321.