Within the scope of the doctoral dissertation, we examined the alloy AlMg6Si2MnZr to investigate the influence of impurities on the metallurgical quality of the melt. A database for numerical simulations was developed for this alloy. Using a specially designed measuring cell for simple thermal analysis, cooling curves were recorded for differently prepared melts based on the primary alloy. These curves were precisely characterized to obtain characteristic temperatures from the solidification range and to estimate the released latent heats. The melts or series of individual samples differed in preparation methods and attempts to incorporate oxide particles (Al2O3). To ensure accurate determination of the sample mass, the measuring cell was placed on a balance. In addition to simple thermal analysis, measurements of electrical resistivity during cooling were also conducted simultaneously in another cell. Insight into the microstructure of all samples was obtained through light and electron microscopy. Due to the complex micro-level structure of the material, thermodynamic calculations were performed for both the base material and derivatives based on the chemical compositions of individual series of samples to provide more precise characterization. Thermodynamic calculations and results of simple thermal analyses were complemented by differential scanning calorimetry. It was found that handling the melt of the material under study during the preparation phase has a significant impact on the final microstructure, leading the manufacturer to likely narrow down the recommended temperature range for use, discourage remelting of the material, and modification or refining of the melt.
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