Caracterização experimental da anisotropia em chapas de alumínio da série 3XXX classe 3104-H34

Abstract

The aluminum alloys processing from refining operations to the final product is associated with a large number of metallurgical phenomena. These phenomena promote variation in the alloys mechanical properties, changing its characteristics and performance. In order to further improve and optimize the processing routes for these alloys, a complete understanding of its behavior during the manufacturing operations execution is required. Thus, the objective of this work was to study the effect of anisotropy on the mechanical characteristics of 3XXX series 3104-H34 class aluminum sheets. To achieve this goal, the microstructure, microhardness, mechanical properties, anisotropic characteristics and conformability parameters of the studied alloy were characterized. The obtained results show that the material microstructure consists of A112Fe3Si and Al6Fe precipitates particles, randomly distributed in the metallic matrix. A112Fe3Si precipitates have elongated geometry with rounded tips on longitudinal section, and faceted tips in the cross section; while Al6Fe precipitates exhibit equiaxial symmetry on both cross and longitudinal section. The Al6Fe-type precipitates volumetric fraction in the cross section is higher than that of the longitudinal, making the cross section hardness values slightly higher than the longitudinal section. The yield tensile strength, ultimate tensile strength and fracture tensile present it maximum values for specimen oriented at 45 ° in relation to the rolling direction, decreasing as the orientation decreases towards 0° and increases to 90°. Young's modulus values showed this same trend. The studied material presented a high normal anisotropy and a low planar anisotropy coefficients values, confirming its suitability for application as a raw material in deep drawing operations. Finally, the values of strength coefficient and strain hardening exponent obtained indicate the studied material high formability, and its lower propensity to suffer fracture during forming.