Tensile properties of AA6061 in different designated precipitation hardening and cold working

In most application of aluminum–magnesium–silicon alloys, both work hardening and precipitation strengthening are important contributors of strength. When these two mechanisms are combined, the additional strengthening mechanism takes place. In this study different designated precipitation hardening and cold working were employed. The 6061 aluminum alloy sheets were subjected to various amounts of reduction in area once or twice. In addition, different precipitation hardening cycles conducted after first and/or second cold rolling. Then tensile properties were evaluated in rolling direction. The results indicated that improvement in mechanical properties and negative or positive effect of pre-aging mainly depend on the amount of cold work. The changes in mechanical properties will be discussed by explanation of microstructural evolution due to precipitation hardening, strain hardening and work softening competition.