Cr12 (quenching and tempering treatment after forging annealing) metallographic diagram

Heat treatment of DIN 1.2080 / X210Cr12 (Alloy forged steel)

The DIN 1.2080 / X210Cr12 is a hard-wearing and high-carbon alloy steel, which is often used for forging purposes. This material is characterised by its high precisions and excellent characteristics such as high-temperature stability, high chromium content and good wear resistance. It is often used for tools and other metal components exposed to harsh working environments. Additionally, the alloy is well-suited for use in air-hardening applications.

In order to achieve the ideal properties, the DIN 1.2080 / X210Cr12 steel is normally alloyed and hardened through a sequence of heat treatments. Through this process, the alloy can be hardened and tempered to a desired degree of hardness and toughness. The typical heat treatment requires a series of steps, such as annealing, tempering, quenching and hardening.

During annealing, the alloy is heated to a temperature between 800°C and 850°C. This heating process aims to reduce the hardness of the material and provide a softer structure. During this process, a slow cooling process is used to relieve any internal stresses.

The second step in the process is tempering. This is done by reheating the material at a temperature that is lower than that used for annealing. The tempering process helps to add ductility and strength to the material.

The quenching step is used to rapidly cool the steel to a temperature of between 50°C and 60°C. The rapid cooling helps to transform the materials into a hardened state. This hardened state is also known as a martensitic transformation.

The DIN 1.2080 / X210Cr12 steel then enters the hardening stage. This involves heating the material to an even higher temperature (between 950°C and 1000°C) compared to the tempering temperature. This results in a further hardening of the material and increases its strength and wear resistance.

In addition to the heat treatment, the DIN 1.2080 / X210Cr12 may also be subjected to a slow cooling process after tempering. This type of heat treatment helps to further reduce the hardening that occurs during the other stages, resulting in a softer and more ductile material.

The DIN 1.2080 / X210Cr12 can also be further processed through regulation of the grains in order to modify the mechanical properties of the material. This is known as creating a microstructure, and is done through the use of an electrolytic polish, where the grain structure is made more uniform by the use of electricity.

Overall, the heat treatment process for the DIN 1.2080 / X210Cr12 involves multiple steps, including annealing, tempering, quenching and hardening. This helps to give the alloy superior characteristics such as high-temperature stability, high chromium content and good wear resistance. The further process of creating a microstructure can further regulate the mechanical properties of the material.

The Cr12(die forging after annealing, quenching and tempering treatment) is a type of high-carbon chromium metal used in the manufacture of various parts or pieces.

It is a popular metal with excellent mechanical properties, like a high hardness, good wear resistance and toughness, good corrosion resistance and heat treatment stability.

Its JIS G4403 special metal standard requires it to have a carbon content between 0.85-1.2%, a chromium content between 11.5-13%, and a C-equivalent content between 0.48-0.54%.

The microstructure of the Cr12 after die forging, annealing, quenching and tempering is generally dual-phase structure. The primary phase is pearlite, which distributes in the area of macro-precipitation and secondary phase of cementite planar micro-precipitation. The core of pearlite is usually a mixture of ferrite and cementite and surrounded by the stable block of cementite. There may also be a small amount of ferrite existing or some other local structure in the primary phase transition area.

On the surface of Cr12, there are many non-metallic inclusions, such as oxides and sulfides, which float in molten metal. If the alloy is quenched too quickly, and the non-metallic inclusions are not enough time to rupture and dissipate, the fractured fragments will remain in the matrix and form martensite and areas. In addition, when the quenching or tempering temperature is too low, or the quenching speed is too slow, the retained austenite transforms into martensite, and then there are martensite-retained austenite lamination regions in the matrix.

In general, the Cr12 with annealing, quenching and tempering treatment can achieve excellent mechanical properties and corrosion resistance, and it is widely used in the manufacture of various valve, fastener, mold and other hard objects.