Which mechanism caused early cast iron Chinese crossbow triggers to fail faster than later bronze versions?

💡 Explanation

Grain boundary carbide precipitation embrittles cast iron because carbon diffuses along grain boundaries and forms brittle carbides, therefore triggers failed readily under stress, rather than the gradual wear of homogenous bronze.

• Which mechanical outcome arises when a historically-constructed rope bridge's hemp fibers experience excessive hygroscopic expansion?
• Within Ptolemaic astronomy, which calculation error resulted when approximating circular orbits to fit observed planetary motion using algebraic methods?
• Which structural response occurs when Roman fortifications experienced differential settlement?
• Which consequence followed when errors by a Quipucamayoc altered Incan textile production records?
• Which computational limitation arose when Inca administrators used quipu made from decayed fibers?
• Which consequence resulted if Incan quipu data were misinterpreted?