First, the principle of selection of lining materials

Intermediate frequency furnace is a kind of heat treatment equipment, usually used to melt superalloy, stainless steel, high chromium steel and other superalloy materials. As the isolation layer between the melting material and the heat source, the furnace lining plays a crucial role in the melting quality and equipment life. Therefore, the following principles should be followed when choosing lining materials:

1. Good high temperature resistance: the temperature in the furnace is high, and it is necessary to choose high temperature resistant materials to ensure that there will be no cracking or deformation of the lining under high temperature conditions.

2. Good wear resistance: In the smelting process, the lining will be affected by the impact and wear of the melting material, and it is necessary to choose materials with good wear resistance to extend the service life of the lining.

3. Good oxidation resistance: At high temperatures, oxidation is very serious, and materials with good oxidation resistance need to be selected to prevent oxidation and corrosion of the lining.

4. No pollution to the smelting material: the selected lining material shall not pollute the smelting material, otherwise it will affect the smelting quality and output.

Second, the classification of lining materials

According to the material characteristics and use, lining materials can be divided into the following categories:

1. Refractory materials: such as refractory brick, refractory board, etc., resistant to high temperature, but not wear-resistant, not heat-resistant impact.

2. Wear-resistant composite materials: such as wear-resistant ceramics, ceramic composite plates, etc., have excellent wear resistance and high temperature resistance, but the price is higher.

3. Magnesia carbon brick: has high temperature strength and heat shock resistance, but poor fire resistance and easy corrosion.

According to the research, for medium frequency furnace smelting high chromium steel, the commonly used lining materials are mainly magnesia-carbon brick, refractory brick and ceramic composite board.

Third, the characteristics and application of different lining materials

1. Magnesia-carbon brick

Magnesium-carbon brick has the advantage of high temperature strength and thermal shock resistance, which is suitable for the case of high furnace temperature. However, due to its insufficient fire resistance, it is easy to corrod the smelting of high chromium steel, and sometimes it will produce a small amount of pollution to the molten material.

2. Firebrick

Refractory brick is a kind of cheap and easy to process furnace lining material, but its wear resistance and thermal shock resistance is relatively poor, easy to crack, rotten brick and other situations, resulting in short life of equipment.

3. Ceramic composite board

Ceramic composite plate is a new type of high efficiency lining material, which has excellent wear resistance, high temperature resistance and corrosion resistance. Its structure is ceramic surface and steel substrate, which can protect the furnace from the wear and corrosion of the smelting material and extend the life of the equipment. However, ceramic composite panels are more expensive and require additional investment.

Iv. Conclusion

Different materials have different effects on the melting quality and equipment life of medium frequency furnace smelting high chromium steel. Therefore, when choosing the lining material, it is necessary to comprehensively consider the characteristics and application of the material, and choose according to the specific production needs and economic conditions. The right material. In practical applications, the requirements for the use of furnace lining materials should be strictly followed, and timely maintenance should be carried out to ensure the stability and long-term operation of the equipment.