Core back of an electrical machine and method for making the same

Core for an axial flow electrical machine comprising a substantially ring shaped coreback and a plurality of teeth, wherein said coreback includes:

• a plurality of stacked, ring shaped sheets of soft magnetic material and
• a barrier of electrical resistance arranged between two adjacent sheets of soft magnetic material for reducing effects of eddy currents,
• wherein each sheet of soft magnetic material in at least a subset of said plurality of stacked, ring shaped sheets of soft magnetic material includes a plurality of first tooth engaging portions and a plurality of second tooth engaging portions, a first tooth engaging portion and a second tooth engaging portion being arranged to at least partially define a tooth opening, and wherein each sheet of soft magnetic material in at least a subset of said plurality of stacked, ring shaped sheets of soft magnetic material further includes a plurality of first outer closing portions and a plurality of second outer closing portions, a first outer closing portion and a second outer closing portion being arranged to face each other between an outer perimeter of said sheet of soft magnetic material and said tooth opening, and
• wherein said plurality of teeth are made of soft magnetic material and each tooth of said plurality of teeth is arranged in a tooth opening and is extending from said coreback in a direction essentially parallel with an axial direction of said coreback.