Determination of flow curve at large cyclic plastic strain by multiaxial forging on MaxStrain System

• We aimed to develop the mechanical model of multiaxial forging.
• Improved physical simulation was applied on Gleeble thermo-mechanical simulator.
• The model provided the possibility of direct calculation of flow curves.
• Flow stress showed lower values by multiple forging than in monotonic deformation.
• Cyclic growing trend observed in evolution of flow stress by multiaxial forging.

In this present work, the determination of flow curve and equivalent strain were aimed by multiaxial forging (cyclic compression test), which was carried out on the MaxStrain System of Gleeble 3800 thermo-mechanical simulator. Therefore, the dimensions of the modifying deformed volume were measured and the surfaces, which are contacted with the tools, were tracked by optical means continuously during the physical simulation. These parameters and the measured force data were applied in the mechanical model, based on the principle of virtual velocities. In the examined range of 0–3 of the equivalent strain, the flow curve of the monotonic deformation is significantly different from the cyclic flow curve. The experiments were performed with AlSi1MgMn heat treatable aluminium alloy at room temperature.