Microstructure and texture evolution of cold rolled 1070 Al alloy during the subsequent annealing treatment

Abstract

The homogenization, cold rolling with the reduction of 85%, and subsequent annealing with various holding time were conducted on 1070 Al alloy. The evolution of microstructure and texture were carefully examined. The electrical conductivity, hardness and tensile test were also carried out. The experimental results indicated that the microstructure during annealing can divided into three stages of recovery, recrystallization and grain growth. With the extension of annealing time, the average grains size continuously increases to 13.95 μm and then decreases to 12.89 μm. The strong {1 1 0} 〈1 1 2〉 Brass, {1 1 1} 〈1 1 2〉 Copper, {1 2 3} 〈6 3 4〉 S and {1 2 4} 〈1 1 2〉 R components and some weak {4 1 4} 〈2 3 4〉 S/Brass and {1 1 0} 〈0 0 1〉 were found in the annealed alloys. The fractions of these texture components varied significantly with the annealing time. The texture intensity increased during recovery process, and decreased with the proceeding of recrystallization. The cold rolled alloy owns the lowest electrical conductivity of 61.4 %IACS, and highest hardness of 45.84 HV. With the extension of annealing time, the conductivity gradually increases and the hardness decreases. Overall, the annealing results in the decrease of tensile strength and the increase of elongation. Keywords: Aluminium alloys, Plasticity methods, Cold rolling, Annealing, Mechanical properties