Metallographic diagram of 12CrlMoV (normalized at 980°C, tempered at 720°C)

CrlMoV is an intermediate in the Cr-Mo series of alloy steel with a tempered martensite. This alloy is most often used in valves, pressure vessels, heat exchangers, and similar items. The CrlMoV alloy is heat treated by preheating to 980°C, followed by a positive temperature hold, and finally cooling in air. This is known as a tempering process and it strengthens the material while allowing greater toughness and ductility.

The CrlMoV alloy is also capable of being heat treated by a process known as annealing. During an anneal, the material is heated to 720°C and held at that temperature for a period of time. This increases strength, hardness and wear resistance, while lowering ductility and toughness.

The CrlMoV alloy is highly corrosion and oxidation resistant. This is due to the high chromium and molybdenum content of the alloy. It is also resistant to pitting and crevice corrosion. This is due to the high levels of chromium and molybdenum that form a protective oxide film on the materials surface.

The CrlMoV alloy has a combination of strength, toughness and ductility. This makes it ideal for applications in high temperature and pressure environments as well as in corrosive environments. The alloy is frequently used in valves, pressure vessels, and heat exchangers but can be used in other applications such as fasteners and rollers.

The CrlMoV alloy is heat treated either by tempering or by annealing. Tempering is done by preheating to 980°C, followed by a positive temperature hold, and cooling in air. This strengthens the material while allowing greater toughness and ductility. Annealing is done by heating to 720°C and holding at that temperature for a time. This increases strength, hardness and wear resistance, while lowering ductility and toughness.

Heat treating is critical for maximizing the performance of the CrlMoV alloy. If the temperature and time of the heat treating process is incorrect, then the performance of the alloy will be compromised. Heat treating should always be performed by an experienced heat treating specialist.

The CrlMoV alloy offers many attractive characteristics for high temperature, high pressure, and corrosive applications. The alloy is highly corrosion and oxidation resistant, pitting and crevice corrosion resistant, and has a combination of strength, toughness and ductility. Heat treating is critical for maximizing the performance of the alloy, and should always be done by an experienced heat treating specialist. The CrlMoV alloy is often used in valves, pressure vessels, and heat exchangers, but can also be used in other applications.

X12CrMoV is a prammo-chromium alloy steel used for automotive components and sport applications. This alloy is quenched and tempered, where the tempering temperature is around 720℃, and hardened by heating to 980℃. This alloy is used to make car engine parts, brakes, pistons and valves.

The X12CrMoV has fine grain structure, high hardness, wear and corrosion resistance, good weldability and thermal properties. The alloy has level machinability, and its strength and ductility can be improved by the addition of alloying elements such as manganese and silicon.

In the heat treatment process, this alloy is heated to 980℃ and quenched, and then tempered at 720℃. This helps to form fine pearlitic structure, and helps to reduce the effects of retained austenite. The hardness of the alloy is between 200 and 350MPa, and the charpy impact strength is greater than 35J at 0℃.

It can be seen in the metallography picture of X12CrMoV that the alloy is composed of tempered martensite. The formed microstructure has the granular shape of tempered martensite, which gives it excellent wear resistance and good heat resistance. The ferrite morphology and lath structure is also observed in the X12CrMoV.

This alloy is widely used in the automotive and sports industry. Its high strength and ductility, good weldability and thermal properties make it suitable for a variety of applications and components.