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Gallium-induced intergranular embrittlement, magnesium enrichment on grain boundary and the degradation of tensile properties of AA6061 Al-Mg-Si alloy after gallium treatment
|關鍵字:||Ai-Mg-Si alloy;鋁-鎂-矽合金;gallium;intergranular fracture;Auger electron spectroscopy;tensile properties;鎵;沿晶破斷;歐傑電子能譜儀;拉伸性質||出版社:||材料科學與工程學系所||引用:||1.P.J.L. Fernandes and D.R.H. Jones, “Mechanisms of liquid metal induced embrittlement”, Int. met. rev., 42 (1997), pp. 251-261. 2.R.C. Hugo and R.G. Hoagland, “Kinetics of gallium penetration into aluminum grain boundaries - in situ TEM observations and atomistic models”, Acta Mater., 48 (2000), pp. 1949-1957. 3.R.C. Hugo and R.G. Hoagland, “In-situ TEM observation of aluminum embrittlement by liquid gallium”, Scripta Mater., 38 (1998), pp. 523-529. 4.W. Ludwig and D. Bellet, “Penetration of liquid gallium into the grain boundaries of aluminum: A synchrotron radiation microtomographic investigation”, Mater. Sci. Eng. A, 281 (2000), pp. 198-203. 5.Y. Liu, and R.G. Hoagland, “Transient and intermittent crack growth during embrittlement of 7075-T651 aluminum by mercury”, Scripta Metall., 23 (1989), pp. 339-344. 6.O. Wouters and J.Th.M.De Hosson, “Lead induced intergranular fracture in aluminum alloy AA6262”, Mater. Sci. Eng. A, 361 (2003), pp. 331-337. 7.N.S. Stoloff and T.L. Johnston, “Crack propagation in a liquid metal environment”, Acta Met., 11 (1963), pp. 251-256. 8.K. Wolski, N. Marie and M. Biscondi, “AES quantification of intergranular film thickness in the Ni-Bi system with respect to the liquid metal embrittlement phenomenon”, Surf. interface anal., 31 (2001), pp. 280-286. 9.J.S. Vetrano, C.H. Henager, Jr., E.P. Simonen, S.G. Song and S.M. Bruemmer, “Interactions between grain boundary sliding and solute segregation in aluminum alloys”, Boundaries and Interfaces in Materials, edited by R.C. Pond, et al., TMS, Indianapolis, (1997), pp. 205-212. 10.A.J. Down, “Chemistry of Aluminum, Gallium, Indium and Thallium”, 1st ed., Chapman & Hall Inc., London, (1993), pp. 14-17. 11.J.E. Hatch, “Aluminum：Properties and Physical Metallurgy”, 3rd ed., American Society for Metals, Ohio, (1984), pp. 1-19. 12.A.K. Vasudevan and R.D. Doherty, “Aluminum alloy-contemporary research and application”, Academic Press Inc., San Diego, 31 (1989), pp. 46-48. 13.M. Murayama and K. Hono, “Pre-precipitate clusters and precipitation processes in Al-Mg-Si alloys”, Acta mater., 47 (1999), pp. 1537-1548. 14.G..A. Edwards, K. Stiller, G..L. Dunlop and M.J. Couper, “The precipitation sequence in Al-Mg-Si alloys”, Acta mater., 46 (1998), pp.3893-3904. 15.I.J. Polmer, “Light Alloys：Metallurgy of the Light Metals”, 3rd ed., Butterworth-Heinemann Inc., Oxford,, (1995), pp. 7-8. 16.J.E. Hatch, in Ref. 11, p 50. 17.A.K. Vasudevan and R.D. Doherty, in Ref. 3, pp.60-64. 18.W.L. Tsai, Y. Hwu, C.H. Chen, L.W. Chang, J.H. Je, H.M. Lin and G.. Margaritondo, “Grain boundary imaging, gallium diffusion and the fracture behavior of Al-Zn alloy - An in situ study”, Nucl. instrum. methods phys. res., B, Beam interact. mater. atoms., 199 (2003), pp. 457-463. 19.C. Elbaum, “Aluminum grain-boundary attack by liquid gallium”, Trans. Met. Soc. , AIME, 215 (1959), pp. 476-478. 20.F.A. Shunk and W.R. Warke, “Specificity as an liquid metal embrittlement”, Scripta Metall., 8 (1974), pp. 519-526. 21.K. Ina and H. Koizumi, “Penetration of liquid metals into solid metals and liquid metal embrittlement”, Mater. Sci. Eng. A, 387-389 (2004), pp. 390-394. 22.P.J.L. Fernandes and D.R.H. Jones, “Effects of microstructure on crack initiation in liquid-metal environments”, Eng. Fail. Anal., 4 (1997), pp. 195-204. 23.M.G. Nicholas and C.F. Old, “Liquid metal embrittlement”, J. Mater. Sci., 14 (1979), pp. 1-18. 24.H.S Nam and D.J. Srolovitz, “Molecular dynamics simulation of Ga penetration along grain boundaries in Al: A dislocation climb mechanism”, Phys. rev. lett., 99 (2007), pp. 025501-025504 25.E.E. Glickman, “Grain boundary grooving accelerated by local plasticity as a possible mechanism of liquid metal embrittlement”, Interface Sci., 11 (2003), pp. 451-459. 26.C.F. Old and P. Trevena, “Liquid metal embrittlement of aluminum single crystals by gallium”, Met. Sci., 13 (1979), pp. 591-596. 27.V.V. Popovich and I.G. Dmukhovskaya, “Rebinder effect in the fracture of armco iron in liquid metals”, Sov.t Mater. Sci., 14 (1978), pp. 365-370. 28.I.G. Dmukhovskaya and V.V. Popovich, “Role of grain size in the molten-metal embrittlement of iron”, Fiziko-Khimichna Mekhanika Materialiv, 16 (1980), pp.42-46. 29.H. Nichols and W. Rostoker, “Mechanism of crack initiation in embrittlement by liquid metal”, Acta Met., 9 (1961), pp. 504-509. 30.G.Nicaise, A.Legris, J.B.Vogt and J.Foct, “Embrittlement of the martensitic steel 91 tested in liquid lead” J. nucl. mater., 296 (2001), pp. 256-264. 31.S.P. Lynch,”Liquid-metal embrittlement in an Al 6% Zn 3% Mg alloy”, Acta Metall., 29 (1981), pp. 325-340. 32.C.M. Preece, “Adsorption-induced embrittlement of metals”, Res. Dev., 23 (1972), pp. 30-34. 33.T.L. Johnston, R.G. Davies and N.S. Stoloff, “Slip character and the ductile to brittle transition of single-phase solids”, Phil. Mag., 12 (1965), pp. 305-317. 34.C.M. Preece and A.R.C. Westwood, “Fracture behaviour of statically loaded metals in liquid metal solutions”, Proceedings of the 2nd international conference on fracture, edited by P.L. Pratt, London, (1969), pp. 439-449. 35.C.M. Preece, A.R.C. Westwood and R.C. Albert, “Temperature-sensitive embrittlement of FCC metals by liquid metal solutions”, Trans. Quart., 62 (1969), pp. 418-425. 36.N.N. Breyer and K.L. Johnson, “Liquid metal embrittlement of 4145 steel by lead-tin and lead-antimony alloys”, J. test. eval., 2 (1974), pp.471-477. 37.B. Joseph, M. Picat and F. Barbier, “Liquid metal embrittlement: A state-of-the-art appraisal”, Eur. Phys. J. Ap. , 5 (1999), pp. 19-31. 38.R.R. Enrique, P.F Becher and L.C. Edgar, “Influence of carbon on the interfacial contact angle between alumina and liquid aluminum”, Surf. interface anal., 35 (2003), pp. 151-155. 39.Z.M. Wang, P. Wynblatt and D. Chatain, “Observation of a sharp transition in contact angle in the wetting of graphite by solid Pb-Ni alloys”, Interface Sci., 7 (1999), pp. 173-180. 40.W. Ludwig, E. Pereiro-Lopez and D. Bellet, “In situ investigation of liquid Ga penetration in Al bicrystal grain boundaries: Grain boundary wetting or liquid metal embrittlement?”, Acta Mater., 53 (2005), pp. 151-162. 41.E.E. Glickman and M. Nathan, “On the kinetic mechanism of grain boundary wetting in metals”, J. appl. physi., 85 (1999), pp. 3185-3191. 42.V.S. Yushchenko, T.P. Ponomareva and E.D. Shchukin, “Environmental influence on the mechanical strength of chemical bonds in solids - ab initio quantum calculations”, J. mater. sci. 27 (1992), pp. 1659-1662. 43.A.R.C. Westwood, “The Rebinder effect and the adsorption-locking of dislocations in lithium fluoride”, Philos. mag., 7 (1962), pp. 633-649. 44.W.M. Robertson, “Propagation of a crack filled with liquid metal”, Trans. Metall. Soc., AIME, 236 (1966), pp. 1478-1482. 45.W.M. Robertson, “Embrittlement of titanium by liquid cadmium”, Met. Trans., 1 (1970), pp. 2607-2613. 46.J. Hopenfeld and W.M. Robertson, “Grain boundary grooving of Type 304 stainless steel and Armco Iron due to liquid sodium corrosion”, Corrosion, 27 (1971), pp. 478-483. 47.E.E. Glikman, Yu.V. Goryunov, “Mechanism of embrittlement by liquid metals and other manifestations of the rebinder effect in metal systems”, Sov. Mater. Sci., 14 (1978), pp. 355-364. 48.W.W. Mullins, “Theory of thermal grooving”, J. appl. physi., 28 (1957), pp. 333-339. 49.W.W. Mullins and P.G. Shewmon, “Kinetics of grain boundary grooving in copper”, Acta Met., 7 ( 1959), pp. 163-170. 50.A.R.C. Westwood and M.H. Kamdar, “Liquid metal embrittlement, particularly of zinc monocrystals by mercury, Philos. Mag., 8 (1963), pp. 787-804. 51.M.H. Kamdar and A.R.C. Westwood, “Effects of alloying on the brittle fracture of zinc in liquid mercury”, Acta Metall., 16 (1968), pp. 1335-1342. 52.S.P. Lynch, “Environmentally assisted cracking: overview of evidence for an adsorption-induced localized-slip process”, Acta Metall., 36 (1988), pp. 2639-2661. 53.S.P. Lynch, “Metal-induced embrittlement of materials”, Mater. charact., 28 (1992), pp. 279-289. 54.V.V. Popovich and I.G. Dmukhovskaya, “Rebinder effect in the fracture of armco iron in liquid metals”, Sov. Mater. Sci., 14 (1978), pp. 365-370. 55.I.G. Dmukhovskaya and V.V. Popovich, “Influence of the adsorption of working media on deformation of solids”, Sov. Mater. Sci., 12 (1976), pp. 394-399. 56.P. Gordon, “Metal-induced embrittlement of metals em dash an evaluation of embrittler transport mechanisms”, Metall. Trans. A, 9A (1976), pp. 267-273. 57.P. Gordon and H.H. An, “Mechanisms of crack initiation and crack propagation in metal-induced embrittlement of metals”, Metall. Trans. A, 13A (1982), pp. 457-472. 58.V. Igoshev, “Micromechanisms of liquid and solid metal induced embrittlement”, Environmentally induced cracking of metals and alloys, edited by M. Elboujdaini et al., Ottawa, (2000), pp. 20-23. 59.R.E. Stoltz and R.H. Stulen, “Solid metal embrittlement of Ti-6Al-6V-2Sn by cadmium, silver and gold”, Corrosion, 35 (1979), pp. 165-169. 60.D.N. Fager and W.F. Spurr, “Solid cadmium embrittlement. Titanium alloys”, Corrosion, 26 (1970), pp. 409-419. 61.S.P. Lynch, “Solid-metal-induced embrittlement of aluminum alloys and other materials”, Mater. Sci. Eng. A, A108 (1989), pp. 203-212. 62.V.S. Smentkowski, “Trends in sputtering”, Prog. surf. sci., 64 (2000), pp.1-58. 63.L.E. Davis, N.C. Macdonald, P.W. Palmberg, G.E. Riach and R.E. Weber, “Handbook of Auger Electron Spectroscopy”, 2nd ed., Physical Electronics Industries Inc., (1976), p13. 64.潘扶民, “材料分析”, 汪建民主編, 第二版, 民全書局, 中國材料科學學會, 台北, (2001), pp. 305-351. 65.M. Katsukura, “Recent trends and future application of aluminum alloys to automobiles”, Light met. age, 59 (2001), pp. 70-73. 66.T. Sakurai and H. Konishi, “Trends and formability issues related to aluminum sheet alloy used for automotive body panels”, Kove Res. Dev., 51 (2001), pp. 9-12. 67.G.S. Daehn, V.J. Vohnout and S. Datta, “Hyperplastic forming: process potential and factors affecting formability”, Materials Research Society Symposium - Proceedings, edited by P. B. Berbon et al., Materials Research Society, 601 (2000), pp. 247-252. 68.A. Kelkar, R. Roth and J. Clark, “Automobile bodies: Can aluminum be an economical alternative to steel?”, JOM, 53 (2001), pp. 28-32. 69.B.Y. Lou, T.D. Wang, J.C. Huang and T.G. Langdon, “On the activation energies observed in Al-based materials deformed at ultrahigh temperatures”, Mater. sci. forum, 357-359 (2001), pp. 545-550. 70.T. Ito, M. Ishikawa, M. Otsuka, M. Saga and M. Kikuchi, “Ductility of 6XXX aluminum alloys at high temperature”, J. Light Metals, 53 (2003), pp. 114-120. 71.A. Joshi, P.W. Palmberg and D.F. Stein, “Role of Mn and Si in temper embrittlement of low alloy steels”, Metall. Trans. A, 6A (1975), pp. 2160-2161. 72.T. Shinoda and T. Nakamura, “Effects of applied stress on the intergranular phosphorus segregation in a chromium steel”, Acta Metall., 29 (1981), pp. 1631-1636. 73.R.D.K. Misra, “Issues concerning the effects of applied tensile stress on intergranular segregation in a low alloy steel”, Acta Mater., 44 (1996), pp. 885-890. 74.J.A.S. Green, W.G. Montague, “Observation on the stress corrosion cracking of an Al-5%Zn-2.5%Mg ternary and various quaternary alloys”, Corrosion, 31 (1975), pp. 209-213. 75.E.C. Pow, J.C. Schwanebeck and W.W. Gerberich, “Hydrogen effect and cadmium segregation to grain boundaries in 7075-T6 aluminum”, Metall. Mater. Trans. A , 9 (1978), pp. 1009-1101. 76.A. Joshi, C.R. Shastry and M. Levy, “Effect of heat treatment on solute concentration at grain boundaries in 7075 aluminum alloy”, Metall. Mater. Trans. A, 12 (1981), pp. 1081-1088. 77.P. Doig, J.W. Edington and M.H. Jacobs, “Microanalaysis across grain boundaries in aluminium alloys”, Philos. Mag., 31 (1975), pp. 285-290. 78.J.M. Chen, T.S. Sun, R.K. Viswanadham and J.A.S. Green, “Grain boundary segregation of an Al-Zn-Mg ternary alloy”, Metall. Trans. A, 9 (1978), pp. 1935-1940. 79.J.E. Hatch, in Ref. 11, pp. 224-240. 80.M. de Hass and J.Th.M. De Hosson, “Grain boundary segregation and precipitation in aluminum alloys”, Scripta Mater., 44 (2001), pp. 281-286. 81.A. Joshi, L.E. Davis and P.W. Palmberg, “Methods of surface analysis, Methods and Phenomena”, Their Applications in Science and Technology, New York, 1 (1975), pp. 159-222. 82.E.D. Hondros and M.P. Seah, “Segregation to interfaces”, Int. met. rev., 22 (1977), pp. 262-301. 83.A. Seiler, L. Schlapbach, T. Von Waldkirch, D. Shaltiel and F. Stucki, “Surface analysis of magnesium-nickel (Mg2Ni)-magnesium, Mg2Ni, and magnesium-copper (Mg2Cu)”, J. less-common met., 73 (1980), pp. 193-199. 84.C. Jardin and D. Robert, “AES and ELS characterization of surface oxides on aluminum-lithium alloys”, Appli. Surf. Sci., 35 (1989), pp. 495-506. 85.E.E. Latta and H.P. Bonzel, “Surface segregation and gas adsorption”, Seminar of the Materials Science Division of ASM on Interfacial Segregation, edited. by W.C. Johnson and J.M. Blakely, ASM, Ohio, (1979), pp. 381-404. 86.C. Lea and C. Molinari, “Magnesium diffusion, surface segregation and oxidation in aluminum - magnesium alloys”, J. Mater. Sci., 19 (1984), pp. 2336-2352. 87.D.T.L. van Agterveld, G. Palasantzas and J.T.M. De Hosson, “Magnesium surface segregation and oxidation in Al-Mg alloys studied with local probe scanning Auger-scanning electron microscopy”, Appli. Surf. Sci., 152 (1999), pp. 250-258. 88.F.J. Esposto, C.S. Zhang, P.R. Norton and R.S. Timsit, “Segregation of Mg to the surface of an Al-Mg single crystal alloy and its influence on the initial oxidation at room temperature”, Surf. sci., 302 (1994), pp. 109-120. 89.J. Bloch, D.J. Bottomley, J.G. Mihaychuk, H.M. van Driel and R.S. Timsit, “Magnesium surface segregation and its effect on the oxidation rate of the (111) surface of Al-1.45at%Mg”, Surf. Sci., 322 (1995), pp. 168-176. 90.H. Ohno, “Making nonmagnetic semiconductors ferromagnetic”, Science, 281 (1998), pp.951-956. 91.A.J. Down, in ref. 10, pp. 106. 92.R.G. Burton and R. A. Burton, “Gallium alloy as lubricant for high current density brushes”, IEEE trans. components hybrids manuf. technol., 11 (1987), pp. 112 -115. 93.J.L. Yang and H.C. Chen, “Serum metabolic enzyme activities and hepatocyte ultrastructure of common carp after gallium exposure”, Zoological stud., 42 (2003), pp. 455-461. 94.S. Izumi, “Environmental safety issues for semiconductors (research on scarce materials recycling)”, Thin Solid Films, 461 (2004), pp. 7-12. 95.E.D. Williams, “Environmental impacts of microchip manufacture”, Thin Solid Films, 461 (2004), pp. 2-6. 96.Y.H. Liao, H.S. Yu, C.K. Ho, M.T. Wu, C.Y. Yang J.R. Chen and C.C. Chang, “Biological monitoring of exposures to aluminium, gallium, indium, arsenic, and antimony in optoelectronic industry workers, J. occup. med., 46 (2004), pp. 931-936. 97.J.Y. Uan and C.C. Chang, “Characterization of gallium-induced intergranular fracture surface and the auger electron spectroscopic analysis for Mg grain boundary segregation in AA6061 T4 Al-Mg-Si alloy”, Mater. Trans., 45 (2004), pp. 1925-1932. 98.R.K. Viswanadham, T.S. Sun and J.A.S. Green, “Grain boundary segregation in Al-Zn-Mg alloys em dash implications to stress corrosion cracking”, Metall. Trans. A, 11A (1980), pp. 85-89. 99.R.G. Song, W. Dietzel, B.J. Zhang, W.J. Liu, M.K. Tseng and A. Atrens, “Stress corrosion cracking and hydrogen embrittlement of an Al-Zn-Mg-Cu alloy”, Acta Mater., 52 (2004), pp. 4727-4743. 100.E. Pereiro-Lopez, W. Ludwig and D. Bellet“Discontinuous penetration of liquid Ga into grain boundaries of Al polycrystals”, Acta Mater., 52 (2004), pp. 321-332. 101.J. Lerner and C.J. McMahon, Jr, “The effect of precipitation hardening on the Hg-induced embrittlement of a Cu-Be alloy”, Mater. Sci. Eng. A, 336 (2002), pp. 72 -74. 102.A. Rolland, M.M. Montagono, L. Roussel and J. Cabane, “Surface segregation of sulphur in pure iron and in FeMo alloys: a comparative AES-radiotracer study”, Appl. Surf. Sci., 108 (1997), pp. 425-432. 103.S. Hofmann, “Depth profiling in AES and XPS. In Practical Surface Analysis：Auger and X-ray Photoelectron Spectroscopy”, 2nd ed., John Wiley & Sons Inc, New York, (1990), pp. 143-199. 104.H. Oechsner, “Sputtering. Review of some recent experimental and theoretical aspects”, Appl. phys., 8 (1975), pp. 185-198. 105.T. Nenadovic, B. Perraillon, Z. Bogdanov, Z. Djordjevic and M. Milic, “Sputtering and surface topography of oxides”, Nucl. instrum. methods phys. res., B, Beam interact. mater. Atoms, B48 (1990), pp. 538-543. 106.V.S. Smentkowski, “Trends in sputtering”, Prog. surf. sci., 64 (2000), pp. 1-58. 107.R.D.K. Misra, C.J. McMahon, Jr. and A. Guha, “Brittle behavior of a dilute copper-beryllium alloy at 200℃ in air”, Scr. metall. mater., 31 (1994), pp. 1471-1474. 108.D. Bika, J.A. Pfaendtner, M. Menyhard and C.J. McMahon Jr., “Sulfur-induced dynamic embrittlement in a low-alloy steel”, Acta Metall. Mater., 43 (1995), pp. 1895-1908. 109.R.D.K. Misra, V. Satya Prasad and P. Rama Rao, “Dynamic embrittlement in an age-hardenable copper-chromium alloy”, Scripta Mater., 35 (1996), pp. 129-133. 110.R.D.K. Misra, “The effect of pre-segregation of phosphorus on the dynamic embrittlement of iron-vanadium alloys at 550℃ in air”, Scripta Mater., 35 ( 1996), pp. 1347-1352. 111.R.D.K. Misra, “Grain boundary segregation and fracture resistance of engineering steels”, Surf. interface anal., 31 (2001), pp. 509-521. 112.R. Stumpf and P.J. Feibelman, “Towards an understanding of liquid-metal embrittlement: Energetics of Ga on Al surfaces”, Phys. rev., B, Condens. matter., 54 (1996), pp. 5145-5150. 113.M. Gupta, L. Adi, V.V. Ganesh and T.S. Srivatsan, “On the use of interconnected reinforcements to enhance the performance of monolithic aluminum”, Current Science, 88 (2005), pp. 1419-1425. 114.B.A. Benson and R.G. Hoagland, “Crack growth behavior of a high strength aluminum alloy during LME by gallium”, Scripta Metall., 23 (1989), pp. 1943-1948. 115.W.Y. Chu, X.M. Liu, J.L. Luo and L.J. Qiao,“Mechanism of embrittlement of Al alloy by liquid metal (Ga)”, Can. metall. q., 38 (1999), pp. 127-132. 116.D. Chatain, E. Rabkin, J. Derenne and J. Bernardini, “Role of the solid/liquid interface faceting in rapid penetration of a liquid phase along grain boundaries”, Acta Mater., 49 (2001), pp. 1123-1128. 117.R.C. Hugo and R.G. Hoagland, “Gallium penetration of aluminum: in-situ TEM observations at the penetration front”, Scripta Mater., 41 (1999), pp. 1341-1346. 118.X.Y. Liu and J.B. Adams, “Grain-boundary segregation in Al-10% Mg alloys at hot working temperatures”, Acta Mater., 46 (1998), pp. 3467-3476. 119.S. Barbagallo, H.I. Laukli, O. Lohne and E. Cerri, “Divorced eutectic in a HPDC magnesium-aluminum alloy”, J. Alloy. Compd., 378 (2004), pp. 226-232. 120.Z. Liu, Y. Bando, M. Mitome and J. Zhan, “Unusual freezing and melting of gallium encapsulated in carbon nanotubes”, Phys. rev. lett., 93 (2004), pp. 095504-1~095504-4. 121.T.B. Massalski, “Binary alloy phase diagrams”, ASM International, 2nd ed., Materials Park, Ohio, (1990), p. 150. 122.B. Joseph, F. Barbier and M. Aucouturier, “Embrittlement of copper by liquid bismuth”, Scripta Mater., 40 (1999), pp. 893-897. 123.A.A. Shirzadi and G. Saindrenan, “New method for flux free diffusion brazing of aluminium alloys using liquid gallium”, Sci. Technol. Weld. Join., 8 (2003), pp. 149-153. 124.A.A. Shirzadi, G. Saindrenan and E.R. Wallach, “Flux-free diffusion brazing of aluminium-based materials using gallium”, Mater. sci. forum, 396-402 (2002), pp. 1579-1584. 125.J.Y. Uan and C.C. Chang, “Gallium-induced magnesium enrichment on grain boundary and the gallium effect on degradation of tensile properties of aluminum alloys”, Metall. Mater. Trans.A, A37 (2006), pp. 2133-2145. 126.S.K. Marya and G. Wyon, “Temporary embrittlement followed by increase in ductility after gallium penetration in cold rolled aluminium”, Scripta Metall., 9 (1975), pp. 1009-1016. 127.S. Schmidt, W. Sigle, W. Gust and M. Ruhle, “Gallium segregation at grain boundaries in aluminium”, Z. Metallk., 93 (2002), pp. 428-431.||摘要:||
The purpose of this dissertation was undertaken to investigate the effect of gallium on the liquid metal embrittlement of aluminum alloy. This work was conducted to develop a pragmatic and satisfactory procedure to promote intergranular cracking for ductile AA6061 Al-Mg-Si alloy at room temperature. The study was also consider the various amount of Ga, holding temperatures and the sample with various rolling directions on the severity of liquid metal embrittlement, respectively. In addition, there remain uncertainties as to the magnitude of the grain boundary chemical composition of AA6061 samples induced by the embrittling agents and its effects on intergranular fracture. To answer these questions, AA1050 sample was used for comparison to determine whether alloying elements would correlate with Ga-induced embrittlement that governed the occurred of intergranular fracture in the AA6061 sample.
According to the SEM observation, the ductile fracture from the samples without any Ga applied on them was observed. The almost fracture surface of samples with Ga was found to be predominantly intergranular. However, intergranular fracture of samples did not occur when the amount of Ga in contact with the sample was less than a critical value. The results proved that the amount of Ga clearly affected the degree of embrittlement of aluminum alloy. The tensile test results showed that the tensile load of Ga-treated sample was significantly higher than that of the samples without any Ga applied on them. When the Ga applied to the samples, the tensile properties of these samples markedly deteriorated. The tensile load and the ratio of dimpled area for the AA6061 sample declines as the amount of Ga applied on them increases. The AES peak-to-peak ratio IMg/IAl showed that the magnesium enrichment on grain boundary is associated with the rolling direction of the sample. Mg enrichment on grain boundaey boundary in the sample whose longitudinal axis was parallel to the rolling direction is relatively weak. A high peak intensity of Mg was observed in the sample whose longitudinal axis is perpendicular to the rolling direction. The AES results also showed that the enrichment of Mg on the grain boundary does not follow from oxidation of the intergranular fracture surface, even though Mg has a high affinity for O. The AES depth profiles indicated that Ga affected the depth profiles of Mg, Al, and O from the surface to the interior. The Mg profile showed a decreasing tendency from the surface to the interior of the sample. In contrast to the Mg profile, the concentration of Ga had a rapid increase from the surface to interior. The reason of embrittlement of Ga-treated AA6061 and AA1050 samples was compared with that of AA1050 sample. The embrittlement of the AA6061 samples with Ga involves a combination of the following two effects: Ga metal on grain boundary embrittlement, and Ga-induced Mg enrichment on grain boundary that further decreases the strength of the grain boundary. However, the behavior of embrittlement of AA1050 sample was occurred due to one of Ga on grain boundary.
In this dissertation examines the effect of Ga on liquid metal embrittlement of aluminum alloys. It provides a new method for fracturing the sample intergranular at room temperature. Moreover, this dissertation was also explained that the amount of Ga, holding temperature and the samples with various rolling directions on the severity of liquid metal embrittlement.
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