This work developed dissimilar friction stir welded joints of AA6082-T6 and AA7050-T7 under different cooling environments namely conventional air, forced air, and water-cooling. Characteristics of developed weld joints were studied for macrostructure, microstructure, microhardness, tensile properties, and fractography. AA6082-T6 dominated in weld nugget macrostructure and proportion of same increased with increasing cooling rate, while weld width reduced remarkably with an increase in heat extraction rate. Welds had interlocking lobes-based flow structures superimposed over an intercalated lamellar layer of both metals. The cooling environment significantly affected the proportion of low/high angle grain boundaries, tensile properties, and hardness of weld nugget zones. The tensile specimens of all-welded joints were fractured from minimum hardness location in a ductile mode.
ThomasWMNicholasED. Friction stir welding for the transportation industries. Mater Des1997; 18: 269–273.
2.
KulekciMKSikA. Effects of tool rotation and transverse speed on fatigue properties of friction stir welded AA 1050-H18 aluminium alloy. Arch Metall Mater2006; 51: 213–216.
3.
ÇamGİpekoğluG. Recent developments in joining of aluminum alloys. Int J Adv Manuf Technol2017; 91: 1851–1866.
4.
Jamshidi AvalH. Influences of pin profile on the mechanical and microstructural behaviors in dissimilar friction stir welded AA6082–AA7075 butt joint. Mater Des2015; 67: 413–421.
5.
FengAHChenDLMaZY. Microstructure and low-cycle fatigue of a friction-stir-welded 6061 aluminum alloy. Metall Mater Trans A Phys Metall Mater Sci2010; 41: 2626–2641.
6.
GuoJFChenHCSunCN, et al. Friction stir welding of dissimilar materials between AA6061 and AA7075 Al alloys effects of process parameters. Mater Des2014; 56: 185–192.
7.
KarakizisPNPantelisDIFourlarisG, et al. Effect of SiC and TiC nanoparticle reinforcement on the microstructure, microhardness, and tensile performance of AA6082-T6 friction stir welds. Int J Adv Manuf Technol2018; 95: 3823–3837.
8.
DursunTSoutisC. Recent developments in advanced aircraft aluminium alloys. Mater Des2014; 56: 862–871.
9.
GibsonBTLammleinDHPraterTJ, et al. Friction stir welding: process, automation, and control. J Manuf Process2014; 16: 56–73.
10.
MengXHuangYCaoJ, et al. Recent progress on control strategies for inherent issues in friction stir welding. Prog Mater Sci2021; 115: 100706.
11.
Reza-E-RabbyMTangWReynoldsAP. Effect of tool pin features on process response variables during friction stir welding of dissimilar aluminum alloys. Sci Technol Weld Joining2015; 20: 425–432.
12.
JunTSDragnevskiKKorsunskyAM. Microstructure, residual strain, and eigenstrain analysis of dissimilar friction stir welds. Mater Des2010; 31: S121–S125.
13.
KumarKKailasSV. Positional dependence of material flow in friction stir welding: analysis of joint line remnant and its relevance to dissimilar metal welding. Sci Technol Weld Joining2010; 15: 305–311.
14.
HuangYXieYMengX, et al. Numerical design of high depth-to-width ratio friction stir welding. J Mater Process Technol2018; 252: 233–241.
15.
HuangYXieYMengX, et al. Joint formation mechanism of high depth-to-width ratio friction stir welding. J Mater Sci Technol2019; 35: 1261–1269.
16.
ZhangZXiaoBLMaZY. Enhancing mechanical properties of friction stir welded 2219al-T6 joints at high welding speed through water cooling and post-welding artificial ageing. Mater Charact2015; 106: 255–265.
17.
LiuHJZhangHJHuangYX, et al. Mechanical properties of underwater friction stir welded 2219 aluminum alloy. Trans Nonferrous Met Soc China2010; 20: 1387–1391.
18.
SharmaCDwivediDKKumarP. Influence of in-process cooling on tensile behaviour of friction stir welded joints of AA7039. Mater Sci Eng A2012; 556: 479–487.
19.
VermaSGuptaMMisraJP. Effect of preheating and water cooling on the performance of friction-stir-welded aviation-grade aluminum alloy joints. J Mater Eng Perform2019; 28: 4209–4220.
20.
CaiBZhengZQHeDQ, et al. Friction stir weld of 2060 Al–Cu–Li alloy: Microstructure and mechanical properties. J Alloys Comp2015; 649: 19–27.
21.
PengGYanQHuJ, et al. Effect of forced air cooling on the microstructures, tensile strength, and hardness distribution of dissimilar friction stir welded AA5A06-AA6061 joints. Metals2019; 9: 304.
22.
DongJZhangDLuoX, et al. EBSD study of underwater friction stir welded AA7003-T4 and AA6060-T4 dissimilar joint. J Mater Res Technol2020; 9: 4309–4318.
23.
BijanrostamiKVatankhah BarenjiR. Underwater dissimilar friction stir welding of aluminum alloys: elucidating the grain size and hardness of the joints. Proc IMechE, Part L: J Materials Design and Applications2019; 233: 763–775.
24.
SinghAUpadhyayV. A study on optimization of welding parameters and their effect on joint properties of dissimilar AA6082-T6 and AA7050-T7 friction stir welds. J Inst Eng Ser D2021; 102: 249–269.
25.
NiuSYueYYanD, et al. Forced cooling friction stir welding of 2060-T8 Al-Li Alloy. J Mater Eng Perform2019; 28: 5763–5771.
26.
DilipJJSKoilrajMSundareswaranV, et al. Microstructural characterization of dissimilar friction stir welds between AA2219 and AA5083. Trans Indian Ins Metals2010; 63: 757–764.
27.
MurrLE. A review of FSW research on dissimilar metal and alloy systems. J Mater Eng Perform2010; 19: 1071–1089.
28.
SatoYSKokawaHEnomotoM, et al. Microstructural evolution of 6063 aluminum during friction-stir welding. Metall Mater Trans A1999; 30: 2429–2437.
29.
MishraRSMaZY. Friction stir welding and processing. Mater Sci Eng R Rep2005; 50: 1–78.
30.
SchneiderJANunesACChenPS, et al. TEM study of the FSW nugget in AA2195-T81. J Mater Sci2005; 40: 4341–4345.
31.
SikAOnderM. Comparison between mechanical properties and joint performance of AA 2024-O aluminium alloy welded by friction stir welding and TIG processes. Met Mater2012; 50: 131–137.
32.
CavalierePDe SantisAPanellaF, et al. Effect of welding parameters on mechanical and microstructural properties of dissimilar AA6082–AA2024 joints produced by friction stir welding. Mater Des2009; 30: 609–616.
33.
MaZYFengAHChenDL, et al. Recent advances in friction stir welding/processing of aluminum alloys: microstructural evolution and mechanical properties. Crit Rev Solid State Mater Sci2018; 43: 269–333.
34.
KrishnanKN. The effect of post weld heat treatment on the properties of 6061 friction stir welded joints. J Mater Sci2002; 37: 473–480.
35.
HassanKAAPrangnellPBNormanAF, et al. Effect of welding parameters on nugget zone microstructure and properties in high strength aluminium alloy friction stir welds. Sci Technol Weld Joining2003; 8: 257–268.
36.
SharmaVSharmaCUpadhyayV, et al. Enhancing mechanical properties of friction stir welded joints of Al-Si-Mg alloy through post weld heat treatments. Mater Today Proc2017; 4: 628–636.
37.
XieYMengXLiY, et al. Insight into ultra-refined grains of aluminum matrix composites via deformation-driven metallurgy. Compos Commun2021; 26: 100776.
38.
XieYMengXChangY, et al. Ameliorating strength-ductility efficiency of graphene nanoplatelet-reinforced aluminum composites via deformation-driven metallurgy. Compos Sci Technol2022; 219: 109225.
39.
MoradiMMJamshidi AvalHJamaatiR, et al. Microstructure and texture evolution of friction stir welded dissimilar aluminum alloys: AA2024 and AA6061. J Manuf Process2018; 32: 1–10.
40.
ChenHFuLLiangP. Microstructure, texture and mechanical properties of friction stir welded butt joints of 2A97 Al Li alloy ultra-thin sheets. J Alloys Comp2017; 692: 155–169.
41.
GhoshMKumarKKailasSV, et al. Optimization of friction stir welding parameters for dissimilar aluminum alloys. Mater Des2010; 31: 3033–3037.
42.
LinHWuYLiuS, et al. Effect of cooling conditions on microstructure and mechanical properties of friction stir welded 7055 aluminium alloy joints. Mater Charact2018; 141: 74–85.
43.
VermaSGuptaMMisraJP. Effect of pin-profiles on thermal cycle, mechanical and metallurgical properties of friction stir–welded aviation-grade aluminum alloy. Proc IMechE, Part B: J Engineering Manufacture2019; 233: 2183–2195.
44.
TanYBWangXMMaM, et al. A study on microstructure and mechanical properties of AA 3003 aluminum alloy joints by underwater friction stir welding. Mater Charact2017; 127: 41–52.
45.
SunTReynoldsAPRoyMJ, et al. The effect of shoulder coupling on the residual stress and hardness distribution in AA7050 friction stir butt welds. Mater Sci Eng A2018; 735: 218–227.
46.
Sree SabariSMalarvizhiSBalasubramanianV, et al. Experimental and numerical investigation on under-water friction stir welding of armour grade AA2519-T87 aluminium alloy. Def Technol2016; 12: 324–333.
