Magnetic pulse welding of metallic tubes – experimental investigation and numerical modelling

Abstract

Magnetic pulse welding (MPW) provides an efficient route to join overlapping metallic tubes by the application of a high magnitude electromagnetic (EM) force. The process is rapidly transient in nature with little scope to comprehend and monitor the evolution of the joint by experimental means. A comprehensive computational process model is presented here to analyse the transient nature of EM field and force, and resulting impact and plastic deformation during MPW of metallic tubes. The computed results are validated with the corresponding experimentally measured weld joint length for specific tube joint geometries. The computed values of the plastic deformation, impact angle and impact velocity along the joint interface are examined further to realise the progressive nature of the joint formation.

Analytical Estimation of Electromagnetic Pressure, Flyer Impact Velocity, and Welded Joint Length in Magnetic Pulse Welding

“…The corresponding reference for each set of data is also indicated in the Tables 5 and 6. For MPW of tubes, the types of coil assembly include single-turn coils [58,59], singleturn coils with a field shaper [10], multi-turn coils [9], and multi-turn coils with a field shaper [7,11,25,33]. In contrast, Table 6 includes the variables for linear flat coils for MPW of sheets.…”

“…Figure 3a shows that the analytically calculated values of the EM pressure for MPW of tubes are in similar order of magnitude with the corresponding reported values with the range of deviations from 1% to 37% considering most of the cases. For example, the analytically computed values of the EM pressure for MPW of AA2017 flyer and SS304 target tubes [58] and electromagnetic forming of AA2024 tubes [59] are 174 and 127 MPa, respectively. The corresponding reported values are 240 [58] and 185 MPa [59], respectively.…”

“…For example, the analytically computed values of the EM pressure for MPW of AA2017 flyer and SS304 target tubes [58] and electromagnetic forming of AA2024 tubes [59] are 174 and 127 MPa, respectively. The corresponding reported values are 240 [58] and 185 MPa [59], respectively. Likewise, the analytically computed values of the EM pressure for MPW of AA6061 flyer and target tubes [9], AA2024 flyer and Cu target tubes [10], and Cu-DHP flyer and 11SMnPb30 steel target tubes [7,33] are close to their corresponding reported values as indicated in Figure 3a.…”

“…5 and 6 for tubes and sheets, respectively. Numerically computed results are taken from references [2,7,[9][10][11]13,33,58]. Analytically computed results are taken from references [25,28,59].…”

“…The corresponding reported values are 300 m/s [7], 320 m/s [11], and 333 m/s [33], respectively. For a slightly higher range of discharge energies, the analytically computed values of the flyer impact velocity for MPW of AA6061 flyer and target tubes [9], AA2024 flyer and Cu target tubes [10], and AA2017 flyer and SS304 target tubes [58] are 669, 608, and 681 m/s, respectively. The corresponding reported values are 660 m/s [9], 625 m/s [10], and 725 m/s [58], respectively.…”