STEEL HAVING NON-MAGNETIC PORTION, ITS PRODUCING METHOD, AND REVOLVING ELECTRIC CORE

摘要

Provided are a steel having a non-magnetic portion, which can be applied to the steel of the remaining portion irrespective of the material and which has a structure of a short treating time required and a determined depth direction, its manufacturing method, and a revolving electric core. There is prepared an electromagnetic steel sheet (10) having a recessed groove. A two-layered chip of a modifier metal foil and a stainless steel foil is so set in the groove of the electromagnetic steel sheet (10) that the electromagnetic steel sheet (10) and the stainless steel foil have surfaces of the same height. The modifier metal foil is melted when electric current is applied under pressure. When this pressing and current applying is continued, inner sides of the electromagnetic steel sheet (10) and the stainless steel foil contacting the modifier metal foil are melted to form a nonmagnetic alloy layer (2) in the region excepting the surface portions of an electromagnetic steel sheet layer (1) and a stainless steel layer (3). The nonmagnetic alloy layer (2) and the stainless steel layer (3) do not pass a magnetic flux.