Materials for engineering, 3rd Edition - (Malestrom)

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Materials for engineering
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Temperature (°C)
Grain size 50 µm 11 µm 8 µm 5 µm
Time
3.1 Change in grain size with normalizing for a ferritic steel.
Recrystallization
If work-hardened metals are annealed at a suitable temperature, a set of new,
undeformed grains will grow by a process of nucleation and growth –
consuming the so-called cold-worked microstructure. The process, known as
recrystallization, is illustrated in Fig. 3.2. If the temperature is raised, or the
annealing prolonged, these new grains grow at the expense of their neighbours
– a phenomenon known as grain growth.
3.2 Recrystallization; new strain-free grains progressively replacing a
cold-worked structure.