Method of forming a rotor

• Main Authors: Wagner, Sean R, Perry, Thomas A, Schroth, James G
• Format: Patent
• Language: English
• Published: 25.02.2020
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; DIFFUSION TREATMENT OF METALLIC MATERIAL; DYNAMO-ELECTRIC MACHINES; ELECTRICITY; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; GENERATION; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION

A method of forming a rotor includes isolating a bridge area of an electrical steel lamination. The bridge area is disposed between a first portion of the electrical steel lamination and a second portion of the electrical steel lamination that is adjacent to the first portion. Each of the first portion, the second portion, and the bridge area has an initial hardness, and the electrical steel lamination has an initial magnetic permeability. After isolating, the method includes hardening only the bridge area so that the bridge area has a treated hardness that is greater than the initial hardness. Concurrent to hardening, the method includes decreasing the initial magnetic permeability at only the bridge area.