中頻感應(yīng)加熱的原理：工件放到感應(yīng)器內(nèi)，感應(yīng)器一般是輸入中頻或高頻交流電 (300-300000Hz或更高)的空心銅管。產(chǎn)生交變磁場(chǎng)在工件中產(chǎn)生出同頻率的感應(yīng)電流，這種感應(yīng)電流在工件的分布是不均勻的，在表面強(qiáng)，而在內(nèi)部很弱，到內(nèi)部接近于0，利用這個(gè)集膚效應(yīng)，可使工件表面迅速加熱，在幾秒鐘內(nèi)表面溫度上升到800-1000℃，但是內(nèi)部溫度比較小

Principle of medium frequency induction heating: the workpiece is placed in the inductor, which is generally a hollow copper tube that inputs medium frequency or high frequency alternating current (300-300000Hz or higher). The alternating magnetic field generates the induction current of the same frequency in the workpiece. The distribution of this induction current in the workpiece is uneven. It is strong on the surface, but weak inside, and close to zero inside. With this skin effect, the workpiece surface can be heated rapidly. The surface temperature rises to 800-1000 ℃ within a few seconds, but the internal temperature is relatively small