Three rolling processes
We differentiate three rolling methods: conventional hot rolling at high forming temperatures, normalizing rolling and thermomechanical rolling. The pre-material is the same for each of the rolling methods: a homogeneously heated slab from the heating furnace with a relatively coarse-grained microstructure.
Two forming sequences
Normalizing rolling consists of two forming sequences. Forming at high temperatures serves the purpose of shaping. Final forming is carried out following a cooling phase.
Effects of normalizing rolling
The grain size is minimized through low forming temperatures because grain growth is greatly reduced during recrystallization. The material grain is refined, and the microstructure is homogenized. The material is subsequently cooled. The steel properties are similar to those of normalized-annealed plates. Further heat treatment is therefore no longer required. This method is the one most frequently used, e.g., for general structural steels, boiler plates and shipbuilding plates.