Abstract:Recycling and reuse of copper alloys constitutes a crucial component in China""s copper alloy production. During the recycling of brass, iron (Fe) is a prevalent impurity element that can significantly impact brass properties, thus necessitating stringent limitation of iron in brass. This study achieved precise control of Fe content during brass recycling by regulating the input of recycled materials, and systematically investigated the influence of iron on microstructure and properties of recycled H65 brass. Results demonstrated that with increasing Fe content in brass, grains were significantly refined, and the ultimate tensile strength, yield strength and plasticity increased. However, this led to a decrease in elongation and electrical conductivity. Specifically, as Fe content increased from 0.014% to 0.051%, the average grain size decreased from 64.2 μm to 48.9 μm, yield strength increased from 105.9 MPa to 122.1 MPa, and hardness increased from 74.5 HV to 88.1 HV. Conversely, elongation decreased from 62.6% to 54.5%, and electrical conductivity decreased from 27.5%IACS to 25.8%IACS. On the other hand, electrochemical tests revealed that the average corrosion rate exhibited an initial decrease followed by an increase, indicating corrosion resistance initially improved but subsequently deteriorated with increasing Fe content. When Fe content was below 0.04%, solid solution strengthening predominated. Further increases may lead to elemental segregation or even precipitation. This research offered systematical guidance for optimizing economic benefits, controlling microstructural evolution, increasing corrosion resistance, and improving processing performance of recycled brass.