Design and Fabrication Analysis on Fracture and Burr Defects of Tin Bronze Outer Layer of Copper-Clad Iron Core and Comparative Research on Shrinkage Defects of Aluminum Bronze

This study aims to reveal the formation mechanisms of typical defects in copper alloy castings and propose targeted process optimization strategies for production quality control. Taking the ZCuSn10P1 tin bronze outer layer of copper-clad iron core as the core research object, typical fracture and burr defects in actual mass production were systematically analyzed via multi-scale characterizations including SEM and EDS. Results show that fracture arises from abnormal Sn segregation and coarse hard-brittle δ phase, while burrs stem from insufficient matrix hardness during machining. Shrinkage cavity and porosity defects of aluminum bronze are further comparatively analyzed. A dual strategy of composition regulation and process optimization is put forward, which can effectively suppress defects and improve product qualification rate. This study provides a reliable reference for quality control and technical upgrading of copper alloy castings.