Which outcome primarily resulted from repeated heating and hammering of copper during ancient bronze tool forging?

💡 Explanation

When copper is repeatedly heated and hammered, work hardening occurs because dislocations accumulate and entangle within the metal's grain structure, leading to grain refinement and increased hardness. Therefore, the material becomes harder rather than more ductile, less brittle, or undergoing a phase transformation, requiring more complex processing.

• Which risk increases when copper used in Early Bronze Age axe heads incorporates high arsenic concentrations?
• Which risk increases when a Roman castrum's wooden palisade defenses are rapidly constructed with unseasoned timber?
• Which structural concern challenged the design of stacked defensive walls around medieval castels and cities?
• Which structural weakness commonly arose during the transition from wooden to iron shipbuilding during the 19th century era?
• Which outcome arises from thermal expansion within a brass framed 18th-century sextant used at sea?
• Which risk increases when the pressure seal in a 19th-century steam engine weakens due to wear?