Ultrasonic assisted friction stir welding (UaFSW) and conventional friction stir welding (FSW) were conducted on AA6061 and Ti6Al4V alloys. Smaller waves and larger flashes were obtained by UaFSW with 20 kHZ frequency and 10 μm amplitude ultrasonics, and the stir zone was expanded as compared to the FSW one. Interfacial micro-cracks were eliminated with the ultrasonic assistance while a mixed zone was formed beside the Al/Ti interface, containing Ti fragment and intermetallic precipitates. As a mixed zone formed with ultrasonics, the UaFSW weld showed doubled strength in the lap shear tests, as compared to the FSW weld. Cracks propagated in the mixed zone weld of the UaFSW weld, whereas propagated along the Al/Ti interface for the FSW weld.
PadhyGK, WuCS, GaoS.Friction stir based welding and processing technologies - process, parameters, microstructures and applications: a review. J Mater Sci Technol. 2018; 34:1–38.
2.
HuangYX, LvZL, WanL, A new method of hybrid friction stir welding assisted by friction surfacing for joining dissimilar Ti/Al alloy. Mater Lett. 2017; 207:172–175.
3.
JiS, NiuS, LiuJ.Dissimilar Al/Mg alloys friction stir lap welding with Zn foil assisted by ultrasonic. J Mater Sci Technol. 2019; 35(8):1712–1718.
4.
SongZ, NakataK, WuA, Influence of probe offset distance on interfacial microstructure and mechanical properties of friction stir butt welded joint of Ti6Al4V and A6061 dissimilar alloys. Mater Des. 2014; 57:269–278.
5.
WanL, HuangY.Friction stir welding of dissimilar aluminum alloys and steels: a review. Int J Adv Manuf Technol. 2018; 99(5-8):1781–1811.
6.
KumarS, WuCS, PadhyGK, Application of ultrasonic vibrations in welding and metal processing: A status review. J Manuf Process. 2017; 26:295–322.
7.
AlinaghianI, HonarpishehM, AminiS.The influence of bending mode ultrasonic-assisted friction stir welding of Al-6061-T6 alloy on residual stress, welding force and macrostructure. Int J Adv Manuf Technol. 2017; 95(5-8):2757–2766.
8.
ZhongYB, WuCS, PadhyGK.Effect of ultrasonic vibration on welding load, temperature and material flow in friction stir welding. J Mater Process Technol. 2017; 239:273–283.
9.
LiuXC, WuCS.Material flow in ultrasonic vibration enhanced friction stir welding. J Mater Process Technol. 2015; 225:32–44.
10.
LiuXC, WuCS.Elimination of tunnel defect in ultrasonic vibration enhanced friction stir welding. Mater Des. 2016; 90:350–358.
11.
ShiL, WuCS, LiuXC.Modeling the effects of ultrasonic vibration on friction stir welding. J Mater Process Technol. 2015; 222:91–102.
12.
PadhyGK, WuCS, GaoS.Precursor ultrasonic effect on grain structure development of AA6061-T6 friction stir weld. Mater Des. 2017; 116:207–218.
LiuXC, WuCS, PadhyGK.Improved weld macrosection, microstructure and mechanical properties of 2024Al-T4 butt joints in ultrasonic vibration enhanced friction stir welding. Sci Technol Weld Joining. 2015; 20(4):345–352.
15.
MuhammadNA, WuCS.Ultrasonic vibration assisted friction stir welding of aluminium alloy and pure copper. J Manuf Process. 2019; 39:114–127.
16.
MaZ, JinY, JiS, A general strategy for the reliable joining of Al/Ti dissimilar alloys via ultrasonic assisted friction stir welding. J Mater Sci Technol. 2019; 35(1):94–99.
17.
LvXQ, WuCS, PadhyGK.Diminishing intermetallic compound layer in ultrasonic vibration enhanced friction stir welding of aluminum alloy to magnesium alloy. Mater Lett. 2017; 203:81–84.
18.
MuhammadNA, WuCS, TianW.Effect of ultrasonic vibration on the intermetallic compound layer formation in Al/Cu friction stir weld joints. J Alloys Compd. 2019; 785:512–522.
19.
YuM, ZhaoH, XuF, Influence of ultrasonic vibrations on the microstructure and mechanical properties of Al/Ti friction stir lap welds. J Mater Process Technol. 2020; 282:116676.
20.
YuM, ZhaoH, JiangZ, Microstructure and mechanical properties of friction stir lap AA6061-Ti6Al4 V welds. J Mater Process Technol. 2019; 270:274–284.
21.
KellyGS, AdvaniSG, GillespieJW, A model to characterize acoustic softening during ultrasonic consolidation. J Mater Process Technol. 2013; 213(11):1835–1845.
22.
LiuXC, WuCS, PadhyGK.Characterization of plastic deformation and material flow in ultrasonic vibration enhanced friction stir welding. Scr Mater. 2015; 102:95–98.
23.
TsengWT.Calculations of lattice parameters and reaction-induced volume and stress changes for Al(Ti) alloys. J Appl Phys. 1996; 79(7):3521–3527.
24.
Gheybi HashemabadS, GuZ, AndoT.Flux-less direct soldering of aluminum by ultrasonic surface activation. J Mater Process Technol. 2016; 233:135–141.
25.
NieKB, WangXJ, WuK, Microstructure and tensile properties of micro-SiC particles reinforced magnesium matrix composites produced by semisolid stirring assisted ultrasonic vibration. Mater Sci Eng A. 2011; 528(29-30):8709–8714.
26.
ChenR, ZhengD, MaT, Effects and mechanism of ultrasonic irradiation on solidification microstructure and mechanical properties of binary TiAl alloys. Ultrason Sonochem. 2017; 38:120–133.
27.
YuM, ZhaoH, JiangZ, Influence of welding parameters on interface evolution and mechanical properties of FSW Al/Ti lap joints. J Mater Sci Technol. 2019; 35(8):1543–1554.
28.
ZhangQ, XiaoBL, WangWG, Reactive mechanism and mechanical properties of in situ composites fabricated from an Al-TiO2 system by friction stir processing. Acta Mater. 2012; 60:7090–7103.
29.
HeuserBJ, TrinkleDR, JalarvoN, Direct measurement of hydrogen dislocation pipe diffusion in deformed polycrystalline Pd using quasielastic neutron scattering. Phys Rev Lett. 2014; 113(2):025504.
30.
NabarroFR.Dislocations in crystals. North-Holland: Oxford; 1979. 466.
31.
NaghaviSS, HegdeVI, WolvertonC.Diffusion coefficients of transition metals in fcc cobalt. Acta Mater. 2017; 132:467–478.
32.
YaoW, WuAP, ZouGS, Formation process of the bonding joint in Ti/Al diffusion bonding. Mater Sci Eng A. 2008; 480(1-2):456–463.
33.
MirjaliliM, SoltaniehM, MatsuuraK, On the kinetics of TiAl3 intermetallic layer formation in the titanium and aluminum diffusion couple. Intermetallics. 2013; 32:297–302.
34.
RamosAR, VieiraA.Kinetics of the thin films transformation Ti-Al multilayer – gamma-TiAl. Surface & Interface Analysis. 2005; 200:326–329.
35.
OhnumaI, FujitaY, MitsuiH, Phase equilibria in the Ti–Al binary system. Acta Mater. 2000; 48:3113–3123.
36.
ZhaoH, YuM, JiangZ, Interfacial microstructure and mechanical properties of Al/Ti dissimilar joints fabricated via friction stir welding. J Alloys Compd. 2019; 789:139–149.
37.
KattnerUR, LinJC, ChangYA.Thermodynamic assessment and calculation of the Ti-Al system. Metall Trans A. 1992; 23A:2081–2090.
