Effects of Gradient Hot Rolled Deformation on Texture Evolution and Properties of 1561 Aluminum Alloy

Abstract

Through gradient hot rolling, a transition zone from the initial undeformed to 30% deformed microstructure was obtained in the 6 mm thick 1561 aluminum alloy hot rolled plate. The effect of gradient deformation on the evolution process of structure and texture characteristics to 1561 aluminum alloy were systematically investigated by X-ray diffractometer (XRD), optical microscope (OM), and electron back-scattered diffraction (EBSD) in this paper. The results showed that after gradient hot rolling, the grains were elongated along the rolled direction, and the average grain size decreased from 18.95 μm to 1.19 μm. After annealing, the average grain size decreased from 28.34 μm to 10.69 μm. The fraction of dynamic recrystallization is low in all cases. With the increase in gradient deformation, the fraction of the deformed texture (110) <100> Goss, (110) <112 > Brass and fiber texture increased under the action of shear strain, the hardness value of annealed 1561 aluminum alloy ranged from 83.8 HV up to as high as 104 HV, and the electrical conductivity (EC) value increased from 23.5% IACS to 24.3% IACS. Significantly, with the increment of the deformation, the dislocation density increases 2.4 × 1013 m−2 of the annealed hot rolled plates, which should be responsible for the hardness increase. While the structure of the alloy becomes more orderly, the EC increases. Work hardening, fine-grain strengthening and texture all influence the mechanical properties of the gradient hot rolled 1561 aluminum alloy plate.