Lower bainite
A low-temperature bainite structure featuring ultrafine carbides precipitated directly inside the ferrite laths. It delivers an outstanding combination of high strength and impact toughness.
Lower bainite forms at lower temperatures and consists of fine ferrite needles with very small carbides. The structure is tough and strong, so it is well suited for highly stressed components. When welding, you have to be careful not to create too much bainite. If the structure is too pronounced, the material can be sensitive to hot cracking, especially under high mechanical stress. To control the structure, you need to control the cooling. It is important that the temperature is not held too long in the critical range and that the material cools evenly. The choice of filler material and heat management play the main role.