Dynamic singular moments in a perfectly conducting mindlin plate with a through crack under a magnetic field

Following Mindlin’z theory of plate bending of magnetoelasticity. we consider the scat-tering of time-harmonic flexural waves by a through crack in a perfectly conducting plateunder a uniform magnetic field normal to the crack surface. An incident wave giving riseto moments symmetric about the crack plane is applied It is assumed that the plate hasthe electric and magnetic permeabilities of ike free space. By the use of Fourier trans-forms we reduce the problem to solving a pair of dual integral equations. The solution ofthe dual integral equations is then expressed in terms of a Fredholm integral equation ofthe second kind The dynamic moment intensity factor versus frequency is computed andthe influence of the magnetic field on the normalized values is displayed graphically. It isfound that the existence qf the magnetic field produces lower singular moments near the crack tip.