Optimization of Aluminum Casting Process Using PLA-Based Casting Patterns and Analysis of their Thermal Behavior

<jats:p>This paper presents the results of experimental and numerical studies of the casting process of 99.85% pure aluminum using investment-casting technologies with patterns produced by additive manufacturing. The influence of pouring temperature, mold-filling time, and gating-system design on porosity formation and casting quality was analyzed. It was established that increasing the pouring temperature within the range of 700–800°C leads to increased porosity due to higher gas solubility and intensified turbulence of the melt flow. It was shown that the separating gating system ensures a minimum number of defects compared to top and bottom metal-feeding systems. In addition, thermal analysis of PLA and a glass-fiber-reinforced PLA composite was carried out. Pure PLA was found to burn out almost completely (residue about 2.4%), whereas the composite was characterized by a high residual content (~43.6%), which may negatively affect mold quality. The simulation results obtained using the AutoCAST software package showed good agreement with the experimental data and confirmed the effectiveness of numerical modeling for optimization of casting processes. It was established that the optimal pouring-temperature range for aluminum is 720–760°C. The obtained results confirm the potential of using PLA in investment casting technology and make it possible to improve the quality of aluminum castings under industrial production conditions.</jats:p>