What are the materials quenched, normalized, annealed, and fired, what are the differences between t

1. Quenching, normalizing, annealing, and tempering are all heat treatment processes of steel, and in order to achieve different properties of the workpiece, the heat treatment process to improve the internal structure of the workpiece is adopted. The difference between them is that the workpiece is heated to different temperatures first, and the workpiece is cooled in different cooling methods and cooling speeds to achieve the purpose of changing the metal structure.

2. Normalizing: Heat the steel or steel parts to the appropriate temperature above the critical point AC3 or ACM for a certain period of time and then cool it in the air to obtain a heat treatment process of pearlitic structure.

3. Annealing: The sub-eutectic steel workpiece is heated to 20-40 degrees above AC3, and after holding for a period of time, it is slowly cooled with the furnace (or buried in sand or lime for cooling) to below 500 degrees and cooled in air.

4. Quenching: a heat treatment process in which the austenitization of steel is cooled at an appropriate cooling rate, so that the workpiece undergoes martensite and other unstable microstructure transformation in all or a certain range within the cross-section.

5. Tempering: The quenched workpiece is heated to an appropriate temperature below the critical point AC1 for a certain period of time, and then cooled by a method that meets the requirements to obtain the required structure and performance.

To increase its carbon content, improve the hardness is called quenching, through qualitative treatment to remove the internal stress is called normalizing, so that the quenched material back to the original hardness is called annealing, the hardness of the material is too high to reduce a little hardness called tempering, quenching + tempering = quenching and tempering. Complete.

Quenching, normalizing, annealing, and fire are all methods to change the metallographic structure of materials, called material quenching and tempering, because the metallographic structure is different, its physical properties are also different, so it must be quenched and tempered according to different uses. It can be distinguished by metallographic analysis, for example, the difference in the structure of the material can be seen under the metallographic microscope.

1.Anneal. The steel is heated to a certain temperature and kept warm at this temperature, then slowly cooled to room temperature

There are several types of annealing, such as complete annealing, spheroidization annealing, and stress relief annealing.

2.Normalizing. The heat treatment process of heating the steel parts to 30-50 above the critical temperature, holding them for an appropriate time, and cooling them in still air is called normalizing.

The main purpose of normalizing is to refine the structure, improve the properties of the steel, and obtain a structure close to equilibrium.

3.Quench. The heat treatment process of heating the steel to a certain temperature above the critical point (the quenching temperature of No. 45 steel is 840-860, and the quenching temperature of carbon tool steel is 760 780), holding it for a certain time, and then cooling it in water (oil) at an appropriate rate to obtain a martensitic or bainite structure is called quenching.

4.Tempering. After the steel is hardened, it is heated to a certain temperature below the critical temperature, kept warm for a certain time, and then cooled to room temperature.

Quenched steel parts generally cannot be used directly, and must be tempered before they can be used. Because of the high hardness and brittleness of quenched steel, brittleness often occurs when used directly.