Which metallurgical outcome arose when Ancient Mesopotamian bronze tools were repeatedly cold-worked?

💡 Explanation

When bronze undergoes repeated cold working, strain hardening occurs because dislocation density increases within the metal's grain structure, impeding further deformation and refining the grain size which increases hardness. Therefore increased hardness because of grain refinement results, rather than increased ductility, embrittlement, or corrosion resistance which involve different atomic-scale/material processes.

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