comprises an undercut in the form of a widened section distanced to the groove opening and the engagement projection and the engagement groove are dimensionally matched to one another in a manner such that the engagement projection and or engagement groove are plastically deformed by way of inserting the engagement projection into the engagement groove so that the engagement projection engages into the widened section of the engagement groove as well as to a method for the manufacture of such a laminated core application_number US 56927005 A description fig1 in a perspective view shows a laminated core according to the present invention in the form of a stator for an electric motor such a stator for example is applied in an electric motor for the drive of a heating circulation pump the stator consists of twelve stator segments 2 the stator segments 2 in the known manner are designed in a t shaped manner with radially inwardly directed pole limbs 4 stator windings not shown here are arranged or wound around the pole limbs 4 pole ring sections 6 extend transversely to the pole limbs 4 on the radial outer side of the stator segments 2 in the peripheral direction the complete stator segments are designed as a laminated core of a multitude of identical laminations 8 stacked on one another as shown the twelve individual stator segments 2 are joined together into a stator ring wherein the individual stator segments 2 in the region of their pole ring sections 6 are connected to one another such that a closed pole ring is formed on the outer periphery of the stator for this engagement projections 10 and engagement grooves 12 are formed on each stator segment on sides or end edges 9 11 of.