Brass is higher than recrystallization temperature of copper

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Reference no: EM13709615

Which one of the following statements is true? Please EXPLAIN

(a) According to the Hall-Petch equation, Ostwald ripening follows the empirical rule:

(d^n)-(d^n(not))=Kt

Where n and K are material-dependent constants, t denotes time, d denotes average grain diameter at time t, and d0 denotes initial average grain diameter.

(b) The recrystallization temperature of brass is higher than the recrystallization temperature of copper.

(d) Recrystallization cannot occur at room temperature.

(e) When a cold worked material is annealed, the microstructure at time t2 is coarser than the microstructure at time t1, if t2 > t1.

Reference no: EM13709615

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