Machine hammer peening (MHP) is a dynamic process to smoothen tool surfaces, increase hardness and introduce residual compressive stresses into the surface layer. Additionally, MHP can be used to apply surface textures that act as lubricant pockets onto tools with specifically shaped hammer heads. These surface textures have proven to minimize friction and decrease wear and tear of sheet metal forming tools. As of now, the wear behavior of these surface textures has not yet been investigated sufficiently in stamping processes. This paper focuses on the application of surface textures by MHP onto stamping tools used for shear cutting operations on a mechanical press. Within the experimental investigations, different textures are applied on the shell area of the stamping tools. During the cutting process, the resulting cutting force is monitored. Based on the force monitoring of the tools the forces are compared after 10000 and 20000 strokes and a correlation analysis between the stroke count as well as wear of the stamping tool, characterized by their functional volumes is conducted. It is shown that MHP induced surface textures are not only capable of reducing wear and tear, but also that the process condition can be monitored by characteristic process values and inline measurements. This allows for an improved tool construction with adapted surface textures and, taking the correlation of the process monitoring data and the wear of the tools into consideration, longer and more plannable maintenance intervals and higher process reliability can be achieved.
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