TY - JOUR
T1 - Revealing microstructural evolution and mechanical properties of resistance spot welded NiTi-stainless steel with Ni or Nb interlayer
AU - Zhang, K.
AU - Shamsolhodaei, A.
AU - Ghatei-Kalashami, A.
AU - Oliveira, J. P.
AU - Zang, C.
AU - Schell, N.
AU - Li, J.
AU - Midawi, A. R. H.
AU - Lopes, J. G.
AU - Yan, J.
AU - Rivera-Díaz-del-Castillo, P. E. J.
AU - Peng, P.
AU - Zhou, Y. N.
N1 - Funding Information:
This work is supported by the Natural Sciences and Engineering Research Council of Canada (NSERC), and Canada Research Chairs (CRC). K. Z. acknowledges support from China Scholarship Council (CSC). J.P.O. acknowledges funding by national funds from FCT - Fundação para a Ciência e a Tecnologia, I.P. in the scope of the projects LA/P/0037/2020, UIDP/50025/2020 and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures, Nanomodelling and Nanofabrication – i3N. The authors acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Beamtime was allocated for proposal I-20210899 EC. The authors also wish to thank Canadian Center for Electron Microscopy (CCEM) at McMaster University for their support for accessing EBSD and TEM. The CCEM is a National Facility supported by NSERC and McMaster University.
Funding Information:
This work is supported by the Natural Sciences and Engineering Research Council of Canada (NSERC), and Canada Research Chairs (CRC) . K. Z. acknowledges support from China Scholarship Council (CSC). J.P.O. acknowledges funding by national funds from FCT - Fundação para a Ciência e a Tecnologia, I.P., in the scope of the projects LA/P/0037/2020 , UIDP/50025/2020 and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures, Nanomodelling and Nanofabrication – i3N. The authors acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Beamtime was allocated for proposal I-20210899 EC. The authors also wish to thank Canadian Center for Electron Microscopy (CCEM) at McMaster University for their support for accessing EBSD and TEM. The CCEM is a National Facility supported by NSERC and McMaster University .
Publisher Copyright:
© 2023
PY - 2024/5/1
Y1 - 2024/5/1
N2 - Dissimilar welding of NiTi and stainless steel (SS) for multifunctional device fabrication is challenging due to the brittle nature of intermetallic compounds (IMCs) that are formed in the weld zone. In this work, Ni and Nb interlayers were applied for the resistance spot welding (RSW) of NiTi and SS to replace the harmful Fe2Ti phase and to restrict the mixing of dissimilar molten metals, respectively. Microstructural evolution and mechanical properties of the joints were investigated. It was shown that a conventional weld nugget was created in the absence of any interlayer in the welded joint suffering from traversed cracks due to the formation of brittle IMCs network in the fusion zone (FZ). By the addition of Ni from the interlayer, Fe2Ti dominated weld nugget was efficaciously replaced by Ni3Ti phase; however, the presence of the large pore and cracks reduced the effective joining area. The use of a Nb interlayer resulted in a fundamentally different joint, in which FZs at NiTi and SS sides separated by the unmolten Nb would suppress the mixing of dissimilar molten metals. Nb-containing eutectic structures with low brittleness formed at the interfaces, contributing to the enhancement of joint strength (increased by 38% on fracture load and 460% on energy absorption). A high-melting-point interlayer showed great potential to realize a reliable and high-performing RSWed NiTi-SS joint.
AB - Dissimilar welding of NiTi and stainless steel (SS) for multifunctional device fabrication is challenging due to the brittle nature of intermetallic compounds (IMCs) that are formed in the weld zone. In this work, Ni and Nb interlayers were applied for the resistance spot welding (RSW) of NiTi and SS to replace the harmful Fe2Ti phase and to restrict the mixing of dissimilar molten metals, respectively. Microstructural evolution and mechanical properties of the joints were investigated. It was shown that a conventional weld nugget was created in the absence of any interlayer in the welded joint suffering from traversed cracks due to the formation of brittle IMCs network in the fusion zone (FZ). By the addition of Ni from the interlayer, Fe2Ti dominated weld nugget was efficaciously replaced by Ni3Ti phase; however, the presence of the large pore and cracks reduced the effective joining area. The use of a Nb interlayer resulted in a fundamentally different joint, in which FZs at NiTi and SS sides separated by the unmolten Nb would suppress the mixing of dissimilar molten metals. Nb-containing eutectic structures with low brittleness formed at the interfaces, contributing to the enhancement of joint strength (increased by 38% on fracture load and 460% on energy absorption). A high-melting-point interlayer showed great potential to realize a reliable and high-performing RSWed NiTi-SS joint.
KW - Intermetallic compounds
KW - Mechanical properties
KW - NiTi
KW - Resistance spot welding
KW - Stainless steel
UR - http://www.scopus.com/inward/record.url?scp=85177837010&partnerID=8YFLogxK
U2 - 10.1016/j.jmst.2023.05.057
DO - 10.1016/j.jmst.2023.05.057
M3 - Article
AN - SCOPUS:85177837010
SN - 1005-0302
VL - 180
SP - 160
EP - 173
JO - Journal of Materials Science and Technology
JF - Journal of Materials Science and Technology
ER -