Low Pb brass rod and manufacturing method thereof

摘要

PROBLEM TO BE SOLVED: To provide a brass bar material reduced in a Pb content, in which cuttability and dezincification resistance are improved without deteriorating its recyclability.SOLUTION: There is provided a brass bar material having a chemical composition comprising, by mass, 60.0 to 66.0% Cu, 0.05 to 0.50% Pb, 0.20 to 0.90% Sn and 0.01 to 0.50% Si, comprising one or more kinds selected from Fe of 0.60% or lower and P of 0.15% or lower in such a manner that the total content of the Fe and P reaches 0.02% or higher, and the balance Zn with inevitable impurities, having a metallic structure where Pb-concentrated particles are dispersed into a matrix made of an α phase and a β phase, and the number density of the Pb-concentrated particles present at the inside of the α phase is 180 pieces/mmor higher to the area of the α phase, and the Sn concentration β(mass%) and the Si concentration β(mass%) in the β phase satisfy 3β+2β≥4.0.SELECTED DRAWING: Figure 1