Spatial distribution of tensile properties in direct chill cast EN AW-5083 alloy ingots

Abstract

The spatial distribution of tensile properties in EN AW-5083 aluminium alloy ingots produced by the semi-continuous Direct Chill (DC) casting process was investigated under industrial conditions. Tensile tests were performed on samples taken from predefined positions within the ingot cross-section according to a Latin square experimental design, enabling systematic evaluation of spatial variability. The analysed parameters included yield strength (R_p0.2) and elongation (A₅₀)_, while the microstructural parameter expressed as the number of grains per unit area (NA) was adopted from previously reported measurements. The results show that both tensile properties vary across the ingot cross-section, with yield strength ranging from 171.5 MPa to 221.0 MPa and elongation from 14 % to 27 %. Despite these local variations, the average values for the front and rear sections of the ingots were very similar, indicating relatively uniform mechanical behaviour along the casting direction. Statistical analysis based on ANOVA revealed that spatial position within the ingot cross-section has a stronger and more consistent influence on elongation than on yield strength. Slice width showed a statistically significant effect on yield strength in the front section, while both slice height and slice width significantly affected elongation. The observed behaviour is associated with non-uniform solidification conditions typical of DC casting, where variations in cooling rate lead to differences in microstructure. Overall, the investigated ingots exhibit a satisfactory level of structural and mechanical homogeneity, and the results contribute to a better understanding of the relationship between solidification conditions, microstructure, and tensile behaviour.