Quantifying Latent Heat in AlSi5Cu Alloys (with 1, 2, and 4% of Cu by Mass) via DSC, Thermal Analysis, and Commercial Software

This study comprehensively evaluates the latent heat of hypoeutectic AlSi5Cu alloys with 1, 2, and 4% of Cu by mass, investigating their solidification behavior under controlled cooling conditions. Latent heat, a critical thermophysical property, significantly influences solidification and microstructural formation in casting processes. The evaluation employed an integrated approach, combining experimental measurements from Differential Scanning Calorimetry (DSC) and thermal analysis (TA-Newtonian method) with computational assessments performed using JMatPro and Thermo-Calc software packages. The findings reveal a reasonable agreement between the measured and calculated latent heat values, suggesting that methods beyond DSC, such as commercial software and thermal analysis techniques, offer acceptable and viable alternatives for determining latent heat in AlSiCu alloys. While DSC served as the experimental reference, providing particularly consistent lowest values for AlSi5Cu1 and AlSi5Cu2, relative error analysis indicated that JMatPro generally yielded results closest to DSC, especially for AlSi5Cu2 (0.245% relative error), and the TA-Newtonian method also showed strong agreement, particularly for AlSi5Cu1 (0.356% relative error) and AlSi5Cu4 (0.787% relative error). Maximum deviation was observed with Thermo-Calc for AlSi5Cu1 (7.474%). These discrepancies are primarily attributed to inherent differences in the underlying thermodynamic databases for computational tools and the sensitivity of experimental techniques to specific material properties and solidification behaviors.