Control Technology for Internal Pinholes and Porosity Defects in Copper Ingot Casting Process

Copper alloy materials play a fundamental role in modern industrial systems. Large-section copper ingots are highly susceptible to thermodynamic and kinetic disturbances during continuous casting, leading to internal shrinkage cavities and micro-porosity defects at the solidification end. A systematic investigation into the mechanisms underlying these metallurgical defects and their mitigation strategies holds significant engineering value. Based on operational data from a high-strength, high-conductivity copper continuous casting project, this study conducts an in-depth analysis of how melt temperature fields, flow fields, and solute distribution influence solid-liquid phase transition processes. The research focuses on key variables—including mold heat exchange efficiency, spatiotemporal distribution of water flux in secondary cooling zones, and conditions of supplementary gating channels at the solidification end—to quantitatively evaluate the impact weights of various process parameters on central density. By implementing targeted control strategies such as nonlinear electromagnetic stirring regulation, dynamic light reduction window definition, and adaptive air-water atomization optimization, the boundary conditions for the copper ingot solidification process were refined. Both metallurgical physical simulations and field experimental data confirm that the optimized approach effectively prevents dendritic bridging, reconstructs equiaxed crystal network structures, significantly reduces the occurrence of macroscopic shrinkage cavities and micro-porosity, and enhances the internal quality stability of the cast ingots.