Spheroidized Cementite

Cementite globules are spherical cementite particles that can appear in the microstructure when the material is annealed for a long time. When welding, they are usually not a big issue as long as you keep the heat input under control and don't stay at temperature unnecessarily long. If you do a stress-relief anneal after welding, make sure the holding time is not excessive, otherwise the microstructure can change unfavorably. Otherwise, the rule is: work cleanly, don't overheat, and let the part cool slowly after welding, then the microstructure stays calm.