There are two methods for burning the graphite molds for the destruction of graphite molds: resistance wire heating method and high -frequency electromagnetic sensing heating method. We know that when the resistance wire heating method is burned, the outer mold temperature is low, and the blade and core mold temperature is higher. The temperature is unevenly decided to decide the part where the mold is destroyed.

1. Surface air oxidation and cracks: Because there is no recovery atmosphere during the entire process of burn, the graphite and gas are directly contacted, and it is difficult to avoid the surface air oxidation at high temperature. The higher the temperature, the faster the air oxidation rate; The mold is slowly consumed, leaving only a part of carbon and gray, and stones can be found on the spot on the spot. After a period of time, the surface of the mold will cause porosity and charcoal.

2. Fracture: The reason for this kind of destruction is that the gear board of the golden steel blade was not firmly clamped, causing unbalanced loss on the top of the head, causing the horizontal shear stress.

3, crushing: Graphite mold immediately touches with base materials with gold and steel. The surface is under pressure. The strength of gold steel and graphite mold is very different. The surface of the mold touched with diamond tool head will cause dentation.

4. Types of knocking down: During the whole process of burning, substrate powder penetrates into the air oxidation gaps of graphite molds in the melting state, causing the adhesion of the special tool head and the middle of the mold to make the mold difficult. The repeated teeth of the mold will make the mold out, which will cause the broken edge of the mold and the dentation of the metal material.

5. The damage specifications of graphite molds are very poor: some substrate powder will squeeze into the surface of the mold under the melting state to adhere to the graphite material. Before applying the mold next time, it is necessary to remove the residual objects of metal materials, which causes the mold and size to go to the tolerance of the mold.