Electrons moving at high speed under an electric field bombard the surface of an object and heat it up. The main component for electron beam heating is the electron beam generator, also known as the electron gun. The electron gun is mainly composed of cathode, beam electrode, anode, electromagnetic lens and deflection coil. The anode is grounded, the cathode is connected to the negative high position, the focusing beam is usually at the same potential as the cathode, and an accelerated electric field is formed between the cathode and the anode. The electrons emitted by the cathode are accelerated to a very high speed under the action of an accelerating electric field, focused by an electromagnetic lens, and then controlled by a deflection coil to make the electron beam shoot towards the heated object in a certain direction.
The advantages of electron beam heating are: (1) control the current value of the electron beam Ie, which can easily and quickly change the heating power; (2) The electromagnetic lens can be used to freely change the heated part or the area of the electron beam bombardment part can be freely adjusted; (3) The power density can be increased so that the material at the bombarded point evaporates instantly.
