Nonoriented electrical steels are silicon steels in which magnetic properties are practically the same in any direction of magnetism in the plane of the material. Standard grades from M-15 to M-47 are available with the advantages of special DI-MAX® processing that enhance the magnetic properties.

DI-MAX grades have superior permeability at high inductions, low average core loss and good gauge uniformity. In addition, cold finishing plus strip annealing produce a smooth surface and reduce buckles and waves, resulting in excellent flatness and a high stacking factor. AK Steel Nonoriented Electrical Steels are available both Fully Processed and Semi-Processed, depending on grade. Properties of Fully Processed material are developed completely by AK Steel. These materials are ready for use without any additional processing required. However, a low-temperature heat treatment may be employed by the user to eliminate stresses introduced by fabrication of the material into cores. AK Steel Fully Processed Nonoriented Electrical Steels meet all the requirements of ASTM Specification A 677.

Semi-Processed steels are finished to final thickness and physical form by AK Steel, but are not fully annealed to develop final magnetic quality. With these materials, achievement of magnetic properties becomes the responsibility of the user. AK Steel Semi-Processed Nonoriented Electrical Steels meet all requirements of ASTM A 683.