At what temperature does regular low-carbon steel transition from BCC to FCC structure?

The transition from Body-Centered Cubic (BCC) to Face-Centered Cubic (FCC) structure in low-carbon steel occurs at approximately 723° C. This temperature is critical in metallurgy as it marks the phase transformation during which iron, when heated, alters its atomic arrangement.

At BCC, which is stable at lower temperatures, atoms are arranged in a way that allows for good strength and toughness. As the temperature increases and reaches around 723° C, the structure begins to transition into FCC, which is denser and can accommodate more carbon. This transition is significant because it impacts the material properties, such as ductility and toughness, which are essential for determining how the steel will behave in various applications.

Understanding this temperature and the corresponding phase transition is crucial for welding and metallurgical processes, as it influences how steel can be heat treated and subsequently welded to achieve desired mechanical properties.