Electromagnetic force assisted fracture of mechanically stressed pre-cracked thin metallic structures was investigated. In absence of any mechanical stress electromagnetic forces at current density j ≥ 4×10~8A/m~2 were observed to cause crack propagation alone, leading to fracture. Finite element analysis showed that stress intensity factor due to electromagnetic forces, K_(IE), varied as K_(IE) = f(a/w)J~2(πa)~(0.5), where f(a/w) is a geometric factor and a is the crack length. The effects of combined loading of electromagnetic forces and far field mechanical stresses can be superimposed, thereby resulting in fracture at smaller current densities under an applied stress. Experimental results validating the above will be shown.
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