Laser Processing Effect On Magnetic Properties Of Amorphous Wires

Controllable, spatially selective treatment of glass-covered amorphous magnetic wires by laser irradiation is demonstrated. Local annealing by an argon laser has resulted in the formation of weakly interacting heterogeneous structures with different magnetic properties. Two large and stable Barkhausen jumps were detected in the magnetization reversal of high and positive magnetostriction wires with treated portions of 200 mum and 0.5 cm. The local annealing of negative magnetostrictive wires has modified wire magnetoimpedance: the maximum of the impedance plot flattens and the working field interval increases. These favorable changes are due to the creation of local stresses and structure interfaces. (C) 2002 American Institute of Physics.