Investigation on damage evolution and acoustic emission behavior of aluminum alloy sheet during blanking process

Premature fracture of aluminum alloy sheet in blanking process will seriously reduce the forming quality and production efficiency of blanking parts. The purpose of this study is to explore the feasibility of using acoustic emission (AE) technique to detect the crack propagation behavior of metal sheet during blanking. AE analysis results provide effective information about plastic deformation and damage evolution. However, this technique cannot determine the depth of internal damage and the state of crack propagation. The displacement field measured by digital image correlation (DIC) method makes it possible to monitor the evolution of strain field and crack initiation during deformation. Therefore, a coupled real-time tracking method of AE and DIC is proposed to measure the deformation and damage evolution process that occur in blanking sheet. Research findings suggest that this method provides a complete and accurate description for the diverse damage evolution process of blanking aluminum alloy sheet. AE is a promising technique used to characterize and quantify the crack propagation process of metallic sheets in blanking.