Structure and Mechanical Properties of Aluminum 1560 Alloy after Severe Plastic Deformation by Groove Pressing

Resumo

The paper analyzes the structure and mechanical properties of sheet-rolled Al 1560 alloy after four cycles of groove pressing. The analysis shows that under quasi-static uniaxial tension at a strain rate of 1 s^-1, the offset yield strength of the groove-pressed alloy and its ultimate strength are respectively 1.4 and 1.5 times higher than their values in the as-received state. The ultimate tensile strain of the alloy after pressing is 17% against 21% in the as-received state, and its microhardness is 2.7 times higher. According to an electron backscatter diffraction analysis, the groove-pressed alloy has a bimodal structure composed of elongated coarse grains and agglomerates of equiaxed grains of micron and submicron sizes. When pressed, the alloy increases the density of its grain boundaries with a misorientation angle of less than 15° and changes its texture from rolling to upsetting whose volume during pressing grows. Part of the grain orientations in both states corresponds to recrystallization. The research data suggest that groove pressing provides grain structure refinement via plastic distortion in Al 15 60 alloy and a considerable increase in its strength properties.