Investigation On Effect Of Zr Element On Al-Cu-Mg-Mn Aluminum Alloy Texture

Al-Cu-Mg-Mn duralumin has been widely applied in aerospace industry because of its excellent specific strength, high specific rigidity and fine deformability. Texture can affect service performance of plates by causing anisotropy on mechanics, deformability, and corrosion resistant. It was an important subject in material research that how to eliminate disadvantageous property and tap aluminium potential by texture adjusting and controlling.By means of texture measurement, microstructure observation as well as TEM observation, the evolvement of Al-Cu-Mg-Mn aluminium alloy texture and the effect of Zr element in the processes of rolling and annealing were investigated in this paper, with the purpose of texture controlling and aluminium alloy service performance improvement. Besides, the connection between LC4 aluminium texture and its anisotropy was studied in simple tension test.The results showed that 50% cold-rolling texture of Al-Cu-Mg-Mn aluminium alloy was random. G{011}<100>component appeared at first and typical "copper-type" appeared whereafter consisted of C{112}<111>component, S{123}<634>component, B{110}<112>component and G{011}<100>component in α,β orientation-line. The intensity of C, B and S components increases with the augmentation of rolling reduction. Intensity of G component increases at beginning and reaches maximum at 70%Re.; the effect of Zr element on the Al-Cu-Mg-Mn aluminum alloy cold-rolling texture was obvious. Extraordinary strong G{011}<100> component and C{112}<111>component, S{123}<634>component and B{110}<112>component appeared with the reduction of 50%. Typical "copper-type" texture appeared and G{011}<100> component disappeared in the process of further cold-rolling. The intensity of C, B and S components decreased with the augmentation of rolling reduction; the recrystallization texture of Al-Cu-Mg-Mn aluminum alloy were random because nucleation process was controlled by PSN, and Zr element had no effect on recrystallization texture, but blocked recrystallization proces; cold-rolling reduction and heating rate did not influence recrystallization texture but affected recrystallizationmisconstruction and double-reduce texture indirectly; texture is closely related to LC4 luminium alloy anisotropy of δ and σ_b and the samples with cold-rolling texture showed obvious anisotropy in δ and σ_b. Schmid factor in 45° direction is higher than that in 0° and 90° directions, it means there has most orientation in this direction and resulted in low δ and σ_b. The orientations with high Schmid factor diminish strength and ratio of elongation and ones with inferior Schmid factor act adversely. "Dense Dislocation Walls (DDWs) Segment Mechanism" was brought forward. Zr element accelerates development of DDWs and subgrains were segmented by DDWs with low reduction, Then, DDWs changes to cell-wall and make orientation of subgrain rotate a wide angle. The subgrains was refine and the cold-rolling texture changed in consequence.