Magnetoelastic delamination buckling of thin ferromagnetic plates

Abstract

The magnetoelastic delamination buckling and growth of thin ferromagnetic plates are analyzed theoretically. The thin ferromagnetic plate with surface normal to a uniform magnetic field is considered to adhere to a non-magnetic substratum. There is assumed to be an initial delamination at the edge or inner part of the plate. The Amperian current model for the magnetization of the ferromagnetic plate is used and the geometrical nonlinearity is included in order to determine the effect of postbuckling stiffness on the delamination growth process. The problem is solved by an asymptotic method, that is, Koiter's initial postbuckling theory. The delamination growth is determined by an energy balance, that is, a Griffith-type criterion. It is found that the magnetoelastic delamination buckling and the growth process depend on the initial delaminated area and the bond strength. Furthermore, the postbuckling behaviour of the initially delaminated ferromagnetic plate is unstable or stable, according to the edge or internal delamination, respectively. The initial imperfections of the buckling mode have a noticeable effect on the postbuckling behaviour and the delamination process of the plate with the edge delamination.