Description

This technical paper examines the critical annealing temperatures of brass wire containing 63.5% to 64.0% copper and their effects on mechanical properties. The research demonstrates that while annealing generally increases elongation and decreases tensile strength up to 600-700°C, a critical temperature around 650°C can cause unfavorable effects, particularly during double annealing processes. At this temperature, the brass transitions from alpha-state to alpha plus beta state, where small quantities of beta microcrystals can act like impurities on alpha microcrystals, leading to reduced tensile strength and elongation. The study concludes that repeated annealing of brass wire should be avoided unless carefully controlled, and manufacturers should either work below or above the critical 650°C temperature region to maintain optimal mechanical properties. The phenomenon is particularly notable because the critical region’s limits are very narrow, and the effects become more pronounced with repeated annealing processes.

Summary done by W/AI.