In order to reduce the current density at the armature throat and enhance the mechanical performance of armature, based on the traditional solid armature structure and the design principle of laminated armature, a design scheme of laminated armature (double-layer armature) structure is proposed, which is more conducive to machining and assembling. The double-layer armature consists of two parts, The throat region is called Part-1, and the rest is Part-2. The two parts form a double-layer armature by mechanical assembly or welding. The electromagnetic force and current density distributions of double-layer C-type and H-type armature are calculated by numerical method, and compared with the results of traditional armature.With the increase of Part-2 resistance, the maximum current density region is transferred from Part-2 to Part-1, which can effectively reduce the current density of armature throat, but excessive resistance will significantly increase the maximum current density of armature. Part-2 should adopt materials with high melting point, good mechanical properties and small difference between resistance and aluminum(R/R_Al<1.4), providing useful reference for armature structure optimization and Performance enhancement.