| 摘要 |
PURPOSE:To manufacture ferromagnetic, long continuous material having uniform coercive force over sufficient length, by measuring cntinuously the coercive forces of ferromagnetic, long continuous material before and after heat treatment, and by controlling the heat treatment temp. so that said coercive forces may attain desired values. CONSTITUTION:AC current is applied to a wire rod 1 passing through magnetized inversion coils 3, 4, in the longitudinal direction of the wire rod 1 so as to generate alternating field, hereby the wire rod 1, a ferromagnetic material, is magnetized, so that the signal is induced in the detecting coils 5, 6 when the wire rod 1 passes through the coils 5, 6. Then the coercive force (Hc) before the heat treatment is determined from the signal of the coil 5 in order to determine the heat treatment temp., and the annealing furnace 2 is controlled using a minicomputer 13 with said temp. The Hc of the wire rod 1 after heat treatment is obtained from the signal of the coil 6 and, if necessary, the heat treatment temp. stored in the computer 13 and the corresponding data of Hc after heat treatment are corrected. As a result, control of the furnace 2 allows to manufacture wire rod having very uniform Hc. |
