Amirkabir University of Technology Amirkabir Journal of Mechanical Engineering 2008-6032 48 2 2016 08 22 Numerical and Experimental Investigation of Electromagnetic Inward Tube Forming in Coupled method Numerical and Experimental Investigation of Electromagnetic Inward Tube Forming in Coupled method 215 226 605 10.22060/mej.2016.605 FA Milad Shabanpour PhD Student, Department of Mechanical Engineering, Amirkabir University of Technology Ali Reza Fallahi Arezoodar Journal Article 2015 05 11 ABSTRACT <br />The coupling of the electromagnetic field and the mechanical structure field is one of the main problems in the theoretical study of Electromagnetic Forming (EMF). In this study, two possible approaches for the simulation of the electromagnetic tube compression forming process were implemented and compared: A loose-coupled and a sequential-coupled algorithm. In the loose-coupled the electromagnetic field and mechanical structure field were solved separately, but in the sequential-coupled algorithm, the electromagnetic simulation and the mechanical structure simulation were iteratively performed by using Maxwell equations and Finite Difference Method (FDM) as subroutine VDLOAD in ABAQUS software. A deformation of the tube and consequently a change in inductance of tube during the process in the sequential-coupled algorithm was considered. The depth of bead in loose-coupled algorithm compared to experimental result had a 35% error, but in a sequential-coupled algorithm this error has been reduced to 5%. To predict tearing in this process Johnson-Cook damage criterion used. Increasing of discharge voltage and tube thickness respectively, had maximum effect on Johnson-Cook damage. Amount of damage less than 0.8 is conservatively suitable for the safe area without fracture. ABSTRACT <br />The coupling of the electromagnetic field and the mechanical structure field is one of the main problems in the theoretical study of Electromagnetic Forming (EMF). In this study, two possible approaches for the simulation of the electromagnetic tube compression forming process were implemented and compared: A loose-coupled and a sequential-coupled algorithm. In the loose-coupled the electromagnetic field and mechanical structure field were solved separately, but in the sequential-coupled algorithm, the electromagnetic simulation and the mechanical structure simulation were iteratively performed by using Maxwell equations and Finite Difference Method (FDM) as subroutine VDLOAD in ABAQUS software. A deformation of the tube and consequently a change in inductance of tube during the process in the sequential-coupled algorithm was considered. The depth of bead in loose-coupled algorithm compared to experimental result had a 35% error, but in a sequential-coupled algorithm this error has been reduced to 5%. To predict tearing in this process Johnson-Cook damage criterion used. Increasing of discharge voltage and tube thickness respectively, had maximum effect on Johnson-Cook damage. Amount of damage less than 0.8 is conservatively suitable for the safe area without fracture. https://mej.aut.ac.ir/article_605_c361bc7b2c033a83d663b8d9fb4be56e.pdf