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Manuscript submitted June 12, 2013.
By using backing plates made out of materials with widely varying thermal diffusivity this work seeks to elucidate the effects of the root side thermal boundary condition on weld process variables and resulting joint properties. Welds were made in 25.4-mm-thick AA6061 using ceramic, titanium, steel, and aluminum as backing plate (BP) material. Welds were also made using a “composite backing plate” consisting of longitudinal narrow strip of low diffusivity material at the center and two side plates of high diffusivity aluminum. Stir zone temperature during the welding was measured using two thermocouples spot welded at the core of the probe: one at the midplane height and another near the tip of the probe corresponding to the root of the weld. Steady state midplane probe temperatures for all the BPs used were found to be very similar. Near root peak temperature, however, varied significantly among weld made with different BPs all other things being equal. Whereas the near root and midplane temperature were the same in the case of ceramic backing plate, the root peak temperature was 318 K (45 °C) less than the midplane temperature in the case of aluminum BP. The trends of nugget hardness and grain size in through thickness direction were in agreement with the measured probe temperatures. Hardness and tensile test results show that the use of composite BP results in stronger joint compared to monolithic steel BP.
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M.Z.H. Khandkar, J.A. Khan, and A.P. Reynolds: Sci. Technol. Weld. Join., 2003, vol. 8, pp. 165–74. CrossRef
P.A. Colegrove, H.R. Shercliff, R. Zettler: Sci. Technol. Weld. Join., 2007, vol. 12, pp. 284–97. CrossRef
H. Schmidt: Ph.D. Thesis, Department of Manufacturing Engineering and Management, DTU, Denmark, 2004.
Rosales MJC, Alcantara NG, Santos J, Zettler R. The Backing Bar Role in Heat Transfer on Aluminium Alloys Friction Stir Welding. MSF. 2010 Jan;636-637:459–64. CrossRef
Nelson TW, Steel RJ, Arbegast WJ. In situ thermal studies and post-weld mechanical properties of friction stir welds in age hardenable aluminium alloys. Science and Technology of Welding & Joining. 2003 Aug 1;8(4):283–8. CrossRef
Su P, Gerlich A, North TH, Bendzsak GJ. Energy utilisation and generation during friction stir spot welding. Science and Technology of Welding & Joining. 2006 Mar 1;11(2):163–9. CrossRef
Bakavos D, Prangnell PB. Effect of reduced or zero pin length and anvil insulation on friction stir spot welding thin gauge 6111 automotive sheet. Science and Technology of Welding & Joining. 2009 Jul 1;14(5):443–56. CrossRef
E112-10 Standard Test Methods for Determining Average Grain Size: Annual Book of ASTM Standards, vol. 313, ASTM, 2007.
Sato YS, Urata M, Kokawa H. Parameters controlling microstructure and hardness during friction-stir welding of precipitation-hardenable aluminum alloy 6063. Metallurgical and Materials Transactions A. 2002 Mar;33(3):625–35. CrossRef
Yan J, Sutton MA, Reynolds AP. Process–structure–property relationships for nugget and heat affected zone regions of AA2524–T351 friction stir welds. Science and Technology of Welding & Joining. 2005 Dec 1;10(6):725–36. CrossRef
Hassan KAA, Prangnell PB, Norman AF, Price DA, Williams SW. Effect of welding parameters on nugget zone microstructure and properties in high strength aluminium alloy friction stir welds. Sci. Tech. Weld. Join. 2003 Aug;8(4):257–68. CrossRef
Simar A, Bréchet Y, de Meester B, Denquin A, Gallais C, Pardoen T. Integrated modeling of friction stir welding of 6xxx series Al alloys: Process, microstructure and properties. Progress in Materials Science. 2012 Jan;57(1):95–183. CrossRef
Gallais C, Denquin A, Bréchet Y, Lapasset G. Precipitation microstructures in an AA6056 aluminium alloy after friction stir welding: Characterisation and modelling. Materials Science and Engineering: A. 2008;496(1–2):77 - 89. CrossRef
Edwards GA, Stiller K, Dunlop GL, Couper MJ. The precipitation sequence in Al–Mg–Si alloys. Acta Materialia. 1998 Jul 1;46(11):3893–904. CrossRef
Svensson L.-E., Karlsson L, Larsson H, Karlsson B, Fazzini M, and Karlsson J: Sci. Tech. Weld. Join., 2000, vol. 5(5), pp. 285–96. CrossRef
D. Bakavos, P.B. Pragnell, and R Dif: Mater. Forum Inst. Mater. Eng., 2004, vol. 28, pp. 124–31.
Hwang RY, Chou CP. The study on microstructural and mechanical properties of weld heat affected zone of 7075-T651 aluminum alloy. Scripta Materialia. 1997 Dec 22;38(2):215–21. CrossRef
- Effect of Backing Plate Thermal Property on Friction Stir Welding of 25-mm-Thick AA6061
- Springer US
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