| 摘要 |
PURPOSE: To provide a core material for an earth leakage breaker having high saturation magnetic flux density and magnetic characteristics of low temperature dependency by employing a microcrystal iron based alloy of specified composition. CONSTITUTION: An iron based alloy containing iron by 60atm.% or more where 50% or more of the entire texture is composed of microcrystal having a grain size smaller than 100nm and having saturation flux density of 1.1T or above and remanence ratio Br/Bs smaller than 0.7 is employed as a core material. A microcrystal core thus produced has very good soft magnetic characteristics of low temperature dependency. It is true for a core having a circular hysteresis loop, i.e., a remanence ratio in the range of 0.4-0.7. Furthermore, an annular core exhibits very good stability for not only pulse level control but also a small superposed DC field. |
