In this work, a novel Ni–Co–Al multi-principal wire was used as only one type of filler material to finish the joining of TA1/Q345 bimetallic sheets by in situ preparation of high-entropy materials in the weld zone (WZ). The results indicated that a good weld formation could be achieved by using the Ni–Co–Al wire. The thermodynamic environment with high mixing entropy (ΔSmix) and low mixing Gibbs free energy (ΔGmix) in the WZ could be created by the Ni–Co–Al wire and the elements introduced from base metals. It could efficiently inhibit the formation of Fe–Ti IMCs and promote the solid-solution structures of FCC and BCC in the WZ. Fe–Ti IMCs were only presented in the transition zones on the TA1 flyer layer as well as a narrow region of the WZ within ∼30 μm away from the Q345/WZ interface, where the ΔGmix was higher than the ΔG of Fe–Ti IMCs.
JiangH, YanX, LiuJ, . Effect of heat treatment on microstructure and mechanical property of Ti–steel explosive-rolling clad plate. T Nonferr Metal Soc. 2014;24:697–704. doi:10.1016/S1003-6326(14)63113-7.
2.
ChaiX, ChengG, ChaiF, . Hot roll bonding between commercially pure titanium and high-strength low-alloy steel using Fe interlayer. J Iron Steel Res Int. 2019;26:1126–1136. doi:10.1007/s42243-019-00322-x.
3.
KunduS, ChatterjeeS.Interfacial microstructure and mechanical properties of diffusion-bonded titanium–stainless steel joints using a nickel interlayer. Mater Sci Eng A. 2006;425:107–113. doi:10.1016/j.msea.2006.03.034.
4.
ZhuZY, LiuYL, GouGQ, . Effect of heat input on interfacial characterization of the butter joint of hot-rolling CP-Ti/Q235 bimetallic sheets by laser + CMT. Sci Rep. 2021;11:10020, doi:10.1038/s41598-021-89343-9.
5.
WangT, ZhangF, LiX, . Interfacial evolution of explosively welded titanium/steel joint under subsequent EBW process. J Mater Process Technol. 2018;261:24–30. doi:10.1016/j.jmatprotec.2018.05.031.
6.
HosseiniSRE, FengK, NieP, . Fracture surface characterization of laser welding processed Ti alloy to stainless steel joints. Weld World. 2018;62:947–960. doi:10.1007/s40194-018-0586-6.
7.
ZhangY, SunDQ, GuXY, . Nd:YAG pulsed laser welding of TC4 Ti alloy to 301L stainless steel using Ta/V/Fe composite interlayer. Mater Lett. 2018;212:54–57. doi:10.1016/j.matlet.2017.10.057.
8.
ChuQ, ZhangM, LiJ, . Experimental investigation of explosion-welded CP-Ti/Q345 bimetallic sheet filled with Cu/V based flux-cored wire. Mater Des. 2015;67:606–614. doi:10.1016/j.matdes.2014.11.008.
9.
NingJ, ZhangL, JiangG, . Narrow gap multi-pass laser butt welding of explosion welded CP-Ti/Q235B bimetallic sheet by using a copper interlayer. J Alloy Compd. 2017;701:587–602. doi:10.1016/j.jallcom.2017.01.129.
10.
ChuQ, TongX, XuS, . The formation of intermetallics in Ti/steel dissimilar joints welded by Cu-Nb composite filler. J Alloy Compd. 2020;828:154389, doi:10.1016/j.jallcom.2020.154389.
11.
ZhangHB, ZhangLJ, LiuJZ, . Microstructures and performances of the butt joint of TA1/Q235B bimetallic sheet with addition of a Mo interlayer by using narrow gap laser welding with filler wire. J Mater Res Technol. 2020;9:10498–10510. doi:10.1016/j.jmrt.2020.07.054.
12.
WuZ, DavidSA, LeonardDN, . Microstructures and mechanical properties of a welded CoCrFeMnNi high-entropy alloy. Sci Technol Weld Joi. 2018;23:585–595. doi:10.1080/13621718.2018.1430114.
13.
MiracleDB, SenkovON.A critical review of high entropy alloys and related concepts. Acta Mater. 2017;122:448–511. doi:10.1016/j.actamat.2016.08.081.
14.
MishraAK, SamalS, BiswasK.Solidification behaviour of Ti–Cu–Fe–Co–Ni high entropy alloys. Trans Indian Inst Met. 2012;65:725–730. doi:10.1007/s12666-012-0206-x.
15.
FuZ, JiangL, WardiniJL, . A high-entropy alloy with hierarchical nanoprecipitates and ultrahigh strength. Sci Adv. 2018;4:8712, doi:10.1126/sciadv.aat8712.
16.
HaoX, DongH, XiaY, . Microstructure and mechanical properties of laser welded TC4 titanium alloy/304 stainless steel joint with (CoCrFeNi)100-xCux high-entropy alloy interlayer. J Alloy Compd. 2019;803:649–657. doi:10.1016/j.jallcom.2019.06.225.
17.
NamH, MoonB, ParkS, . Gas tungsten arc weldability of stainless steel 304 using CoCrFeMnNi filler metals for cryogenic applications. Sci Technol Weld Joi. 2021;27:33–42. doi:10.1080/13621718.2021.1996851.
18.
LiuD, WangW, ZhaX, . Effects of groove on the microstructure and mechanical properties of dissimilar steel welded joints by using high-entropy filler metals. J Mater Res Technol. 2021;13:173–183. doi:10.1016/j.jmrt.2021.04.060.
19.
DengYQ, ShengGM, HuangZH, . Microstructure and mechanical properties of diffusion bonded titanium/304 stainless steel joint with pure Ag interlayer. Sci Technol Weld Joi. 2013;18:143–146. doi:10.1179/1362171812Y.0000000083.
20.
ChuQ, ZhangM, LiJ, . Intermetallics in CP-Ti/X65 bimetallic sheets filled with Cu-based flux-cored wires. Mater Des. 2016;90:299–306. doi:10.1016/j.matdes.2015.10.136.
21.
EsfahaniMRN, CouplandJ, MarimuthuS.Numerical simulation of alloy composition in dissimilar laser welding. J Mater Process Technol. 2015;224:135–142. doi:10.1016/j.jmatprotec.2015.05.005.
22.
OliveiraJP, ZengZ, AndreiC, . Dissimilar laser welding of superelastic NiTi and CuAlMn shape memory alloys. Mater Des. 2017;128:166–175. doi:10.1016/j.matdes.2017.05.011.
23.
WangX, LuoY, FanD.Investigation of heat transfer and fluid flow in high current GTA welding by a unified model. Int. J. Therm. Sci. 2019;142:20–29. doi:10.1016/j.ijthermalsci.2019.04.005.
24.
LuS, FujiiH, NogiK.Marangoni convection and weld shape variations in Ar–O2 and Ar–CO2 shielded GTA welding. Mater Sci Eng A. 2004;380:290–297. doi:10.1016/j.msea.2004.05.057.
25.
HuangW, WangH, RinkerT, . Investigation of metal mixing in laser keyhole welding of dissimilar metals. Mater Des. 2020;195:109056, doi:10.1016/j.matdes.2020.109056.
26.
LiuD, WangW, ZhaX, . Experimental investigation of butt welded Ti/steel bimetallic sheets by using multi-principal powders as a single filler metal. J Mater Res Technol. 2021;15:1499–1512. doi:10.1016/j.jmrt.2021.09.004.
27.
TangY, WanN, ShenM, . A comparison of the microstructures and hardness values of non-equiatomic (FeNiCo)-(AlCrSiTi) high entropy alloys having thermal histories related to laser direct metal deposition or vacuum remelting. J Mater Res Technol. 2021;15:696–707. doi:10.1016/j.jmrt.2021.08.046.
28.
ZhangY, ZhouYJ, LinJP, . Solid-Solution phase formation rules for multi-component alloys. Adv Eng Mater. 2008;10:534–538. doi:10.1002/adem.200700240.
29.
GuoS, LiuCT.Phase stability in high entropy alloys: formation of solid-solution phase or amorphous phase. Prog Nat Sci Mater Int. 2011;21:433–446. doi:10.1016/S1002-0071(12)60080-X.
30.
GuoS, ChunNG, LuJ, . Effect of valence electron concentration on stability of fcc or bcc phase in high entropy alloys. J Appl Phys. 2011;109:103505, doi:10.1063/1.3587228.
31.
MurrayJL.Phase diagrams of binary titanium alloys. ASM Int. 1987;99:340–345.
32.
YangX, ZhangY.Prediction of high-entropy stabilized solid-solution in multi-component alloys. Mater. Chem. Phys. 2012;132:233–238. doi:10.1016/j.matchemphys.2011.11.021.
33.
HeB, ZhangNN, LinDY, . The phase evolution and property of FeCoCrNiAlTix high-entropy alloying coatings on Q253 via laser cladding. Coating. 2017;7:157, doi:10.3390/coatings7100157.
34.
ChenX, GaoD, ZhangY, . Evolution of microstructures and compressive properties in Al0.5CrFeNi2.1Mn0.8Tix high entropy alloys. Met Mater Int. 2020;27:118–126. doi:10.1007/s12540-020-00620-0.
35.
LiuD, GuoR, HuY, . Effects of the elemental composition of high-entropy filler metals on the mechanical properties of dissimilar metal joints between stainless steel and low carbon steel. J Mater Res Technol. 2020;9:11453–11463. doi:10.1016/j.jmrt.2020.08.028.
36.
ChuQ, XiaT, ZhangL, . Structure-Property correlation in weld metals and interface regions of titanium/steel dissimilar joints. J. Mater. Eng. Perform. 2022. doi:10.1007/s11665-022-06693-9.
