Morphology evolution and agglomeration mechanism of Fe5Si3 precipitated phase after Fe[sbnd]Si microalloying and its effect on the properties of brasses

Abstract

The regeneration of scrap brass is affected by the impurity elements in raw materials. It is of practical significance to clarify the interaction of trace elements in brass melt for efficient recovery of scrap brass. The effect of FeSi microalloying on microstructure evolution and properties of as-cast H62 brass was investigated in the present study. The experimental results indicated that the microstructure of H62 brass containing 0.4 wt% Fe changed obviously after the introduction of silicon element. The volume fraction of Fe-rich phase increased with the increase of Si content, and the introduction of Si intensified the agglomeration behavior of Fe-rich phase. The thermodynamic analysis indicated that the silicon showed strong reactivity and bonding ability, and theoretical calculation suggested that silicon preferentially bonded with iron in melt to form new atomic clusters. The introduction of silicon also changed the morphology of the precipitated phase. The influence of silicon addition on the morphology evolution of FeSi precipitated phase was studied. The above reasons should be responsible for the microstructure evolution of as-cast brass. In addition, the mechanical properties and electrical conductivity of the microalloyed brass were tested. This study provides a new insight into the regulation of microalloying elements in regenerated brass.