S-N BEHAVIOUR OF FRICTION STIR WELDED AZ31B MAGNESIUM ALLOY JOINTS
Keywords:
Magnesium alloy, Friction stir welding, FatigueAbstract
Friction stir welding (FSW) is a relatively new joining technique particularly for magnesium and aluminum alloys that are difficult to fusion weld. In this paper, an excellent friction stir weld of rolled AZ31B magnesium alloy joints were obtained at proper process parameter. The base metal and welded joints of AZ31B were analyzed using on optical microscopy, scanning electron microscopy (SEM), tensile testing, fatigue properties and Vickers microhardness measurements. Fatigue experiment was conducted using computerized servo hydraulic controlled fatigue testing machine (INSTRON-8801). Fatigue strength, fatigue notch factor and notch sensitivity factor were evaluated. Fatigue properties of AZ31B welded joints were evaluated, and it was found that the fatigue strength of AZ31B welded joints is 46Mpa which is approximately 34 % lower than that of the base metal fatigue strength due to friction stir welding process.
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References
Edgar R L (2000), “Magnesium Alloys and their Application”, (K.U. Kainer Pub., France,) p.3.
Su S F Huang J C Lin H K Ho N J (2002), “Electron-beam welding behavior in Mg–Albased alloys”, Metall Mater Trans A, Vol.33(A),1461–73.
Lee W B Kim J W Yeon Y M Jung S (2003), “The joint characteristics of friction stir welded AZ91D magnesium alloy”, Mater Trans, Vol.44, 917–23.
Magnesium and magnesium alloy (1999), ASM Specialty Hand book, ASM International, pp 194–199.
Afrin N Chen D L Cao X Jahazi M (2008), “Microstructure and tensile properties of friction stir welded AZ31B magnesium alloy”, Mater Sci., Eng., Vol. 472 (A),179–186.
Padmanaban G Balasubramanian V SarinSundar J K (2010), “Influences of Welding Processes on Microstructure Hardness and Tensile Properties of AZ31B Magnesium Alloy”, JMEPEG DOI: 10.1007/s11665-009-9389-7.
Tokaji K Kamakura M Ishiizumi Y Hasegawa N (2004), “Fatigue behaviour and fracture mechanism of a rolled AZ31 magnesium alloy”, International Journal of Fatigue, Vol. 26, 1217–1224.
Lu Y Z Wang Q D Ding W J Zeng X Q Zhu Y P (2000), “Fracture behavior of AZ91 magnesium alloy”, Materials Letters, Vol. 44, 265–268.
Eisenmeier G Holzwarth B Hoppel H W Mughrabi H (2001), “Cyclic deformation and fatigue behaviour of the magnesium alloy AZ91”, Materials Science and Engineering ,Vol.(A) 319–321, 578–582.
Wolf B Fleck C Eifler D (2004), “Characterization of the fatigue behaviour of the magnesium alloy AZ91D by means of mechanical hysteresis and temperature measurements”, International Journal of Fatigue, Vol.26, 1357–1363.
Dieter G E (1988)“Mechanical metallurgy”,Tata McGraw Hill: New York.
Jaccard R (1990), “Fatigue crack propagation in aluminium”, IIW Doc XIII, p. 1377–90.
Sonsino C M (1999),“Fatigue assessment of welded joints in Al–Mg–4.5Mn aluminium alloy AA 5083 by local approaches”, Int J Fatigue, Vol. 21,985–99.
Courtney T H (2000), “Mechanical behaviour of materials”, 4th ed. McGraw Hill, New York.
Padmanaban G Balasubramanian V “An experimental investigation on friction stir welding of AZ31B magnesium alloy”, Int J AdvManufTechnol, DOI 10.1007/s00170-009-2368-1.
Wang X H Wang K S (2006), “Microstructure and properties of friction stir butt-welded AZ31 magnesium alloy”, Mater Sci., Eng A, Vol. 431,114–117.
Esparza J A Davis W C Trillo E A Murr L E (2002), “Friction stir welding of magnesium alloy AZ31B”, J Mater Sci., Lett, Vol. 21,917.
Padmanaban G Balasubramanian V (2010) , “Fatigue performance of pulsed current gas tungsten arc, friction stir and laser beam welded AZ31B magnesium alloy joints”, Materials and Design, Vol. 31, 3724–3732.
Hertzberg R W (1983), “Deformation and fracture mechanics of engineering materials”, John Wiley & Sons.
Fuchs H O Stephens R I (1980) “Metal fatigue in engineering”, John Wiley & Sons.
Potluri N B Ghosh P K Gupta P C Reddy Y S (1996), “Studies on weld metal characteristics and their influences on tensile and fatigue properties of pulsed current GMA welded Al–Zn–Mg alloy”, Weld Res Suppl., Vol. 62s–70s.
