| 摘要 |
PURPOSE:To improve reproducibility and mass-productivity by coating an alloy thin sheet core provided with a magnetic gap and a closed magnetic path with a nonmagnetic metallic plating film. CONSTITUTION:15 denotes a thin sheet core of a ''Sendust'' alloy composed of 6.2wt% Al, 9.6wt% Si, and 84.2wt% Fe. The core 15 is beforehand deposited with an SiO2 film 6'' of about 0.2-0.3mum by a sputtering method, etc. on the magnetic gap 6' between the upper corner parts 4', 5' which are brazed to face each other for the need of facilitating the plating operation by adhering securely core blocks 2' and 3' in the case of butting said core blocks. An Ni-P alloy film 16 as a nonmagnetic metallic plating film is formed by immersing the core 15 in an electroless nickel plating soln. to be subjected to hypophosphite reduction to coat the plating film over the entire surface thereof then polishing the end face covering the gap 6' until the gap 6' is exposed. Since the alloy core is coated and reinforced by the nonmagnetic metallic plating film in the above- mentioned way, the coating is easily accomplished without requiring another reinforcing member and without requiring the stage for sandwiching and assembling the core. |
