What is the function of a box type tempering furnace?

Box type tempering furnace is a key equipment in heat treatment process, which improves the performance of metal materials by precisely controlling temperature and time for tempering treatment.

1. Eliminate internal stress and stabilize workpiece size
Working principle: Metal materials will generate internal stress during quenching and other processing, causing deformation or cracking of the workpiece. The box type tempering furnace heats the workpiece to a certain temperature and keeps it warm, rearranging the atoms inside the material and releasing internal stress.
Application scenarios:
High precision parts, such as precision gears and molds in the aerospace industry, require tempering to eliminate internal stress and ensure dimensional stability.
Large workpieces, such as the main shaft of wind power equipment and the crankshaft of ship engines, can be tempered to avoid deformation during subsequent processing or use.

2. Adjust material organization and performance
Grain refinement: Tempering can promote the precipitation and distribution of carbides in the material, refine the grain structure, and improve the toughness and strength of the material.
Improve overall performance:
Balance between hardness and toughness: For example, tool steel has high hardness but high brittleness after quenching, and tempering can reduce hardness and improve toughness, making it both wear-resistant and impact resistant.
Optimize physical properties, such as improving the permeability of magnetic materials and reducing the resistivity of resistive materials.

3. Improve material processing performance
Softening material: The hardness of the quenched material is too high, making it difficult to perform cutting processing. Tempering can reduce hardness, improve material machinability, and reduce tool wear.
Improving cold deformation performance: For materials that require cold processing (such as cold drawing, cold rolling), tempering can reduce deformation resistance and avoid cracking during processing.

4. Meet special process requirements
Low temperature tempering (150-250 ℃):
Application: Final heat treatment of tool steel and mold steel.
Effect: Maintain high hardness and wear resistance while reducing brittleness.
Medium temperature tempering (350-500 ℃):
Application: Heat treatment of spring steel and elastic components.
Effect: Achieve high elastic limit and yield strength.
High temperature tempering (500-650 ℃):
Application: Quenching and tempering treatment of structural steel and mechanical parts.
Effect: Make the material have good comprehensive mechanical properties.

5. Ensure the quality and reliability of workpieces
Uniform heating: The box type tempering furnace adopts zone temperature control technology to ensure uniform heating of all parts of the workpiece and avoid performance differences caused by temperature gradients.
Accurate temperature control: The high-precision temperature control system (± 1-5 ℃) can meet the tempering process requirements of different materials, ensuring product quality stability.
Reduce defects: By optimizing the tempering process, defects such as oxidation and decarburization on the surface of the workpiece can be reduced, and the surface quality can be improved.

6. Summary
The box type tempering furnace plays an irreplaceable role in eliminating internal stress, adjusting microstructure, improving processing performance, meeting special process requirements, and ensuring workpiece quality by precisely controlling temperature and time for tempering metal materials. It is one of the key equipment in modern manufacturing industry to ensure stable performance of metal materials and improve product quality.