Evaluating the Suitability of ADC12 for Sand Casting: Filling, Solidification, and Mechanical Properties

This research investigates the applicability of ADC12 aluminum alloy in sand casting processes and compares its casting behavior and performance with that of conventionally sand-cast alloys such as A356 and AlSi10Mg. ADC12 is primarily utilized in high-pressure die casting (HPDC) and low-pressure die casting (LPDC) due to its excellent castability, pressure tightness, and favorable mechanical properties in thin-walled components. However, its use in sand casting is minimal globally, primarily due to the alloy’s high silicon and iron content, which can lead to poor feeding characteristics, increased porosity, and structural non-uniformity in non-pressurized molds. In this study, 3 mm thick test castings were produced using conventional sand casting methods, with particular attention to mold and core design to simulate challenging flow and solidification conditions. Comparative castings of A356 and AlSi10Mg were also produced under identical conditions to establish performance baselines. The objective was to evaluate the filling behavior, solidification characteristics, and final casting quality of ADC12 in sand molds, and to determine its potential for use in applications where die casting is not viable. A comprehensive evaluation was conducted covering key casting parameters: Fluidity and mold filling behavior (evaluated through flow pattern simulations and casting trials) Casting defects and internal integrity (analyzed using real-time X-ray radiography and defect quantification techniques). Density Index (DI) to assess gas entrapment and hydrogen porosity. Mechanical properties, including tensile strength, yield strength, elongation, and hardness (tested according to ASTM standards). Microstructural characterization via optical microscopy and SEM/EDS to examine grain structure, silicon morphology, and intermetallic phases. Fractography of failed tensile specimens to understand failure modes and defect influence. Preliminary results indicate that although ADC12 exhibits higher susceptibility to porosity and reduced ductility in sand cast form compared to A356 and AlSi10Mg, it is still capable of producing structurally acceptable components with optimized gating and venting designs. The study contributes new insights into the adaptability of ADC12 for sand casting, expands the material selection range for low-volume or prototype production scenarios, and provides a technical basis for further optimization of casting parameters to enhance the performance of ADC12 in sand mold applications.