| 摘要 |
PURPOSE:To manufacture ferromagnetic, long continuous material having uniform reluctivity over sufficient length, by measuring continuously the reluctivity of a ferromagnetic, long continuous material before and after heat treatment, and by controlling the heat treatment temp. so that these reluctivity values may attain desired values. CONSTITUTION:The reluctivity (rhoalpha) of long wire rod 1, made of e.g. semihard magnetic material, before and after the heat treatment 2 is measured continuously, and the heat treatment temp. is controlled with rhoalpha obtained before and after the heat treatment. That is, electric current for measurement is applied from a mercury cell 15 through a rotary electrode pairs 5, 6 to the wire rod 1, and the electric current for measurement is detected by measuring the voltage drop of a standard resistance 13 correctly. Under the conditions, the voltage drop due to the wire rod is measured with rotary electrode pairs 9, 10, and said detected value and said measured value are digitized through detecting amplifiers 20, 18 by an AD converter 22 and are fed to a minicomputer 24. Subsequently, an electric current is applied from a pulse oscillator 17 to the coil 3 to generate a magnetic field, and said both voltages at that time are detected thereby determining rhoalpha with these values. The rhoalpha after heat treatment is measured in the same manner, and the rhoalpha allows to control the rhoalpha of the wire rod 1 after heat treatment 2. |
