Which outcome occurs when inadequately quenched high-carbon cast iron is rapidly cooled in ancient Chinese foundries?

💡 Explanation

Formation of martensite occurs because rapid cooling introduces lattice strain, preventing equilibrium carbon diffusion. Therefore a hard, and brittle phase transformation occurs, rather than the softer, more ductile phases which would form during slower cooling.

• Which risk rises when Roman legionary siege catapults remain overwound?
• Which risk increases during repetitive firing if early Chinese crossbow trigger mechanisms, cast from brittle grey cast iron, were improperly heat treated?
• Which outcome arises when wrought iron chains supporting a historical suspension bridge experience prolonged fluctuating tensile forces?
• Which consequence arises when a Medieval siege crossbow's tiller weakens?
• Which structural weakness increased when 18th-century shipbuilders rapidly assembled green timber hulls?
• Which outcome results when roadbed compaction fails under Roman roads?