Grinding Strategies for Local and Stress Orientated Subsurface Modification of Sheet-Bulk Metal Forming Tools

Kategorien Zeitschriften/Aufsätze (reviewed)
Jahr 2020
Autoren Keitel, M., Denkena, B., Krödel-Worbes. A.:
Veröffentlicht in Industrial Colloquium of the Transregional Collaborative Research Centre 73; TCRC73 2020: Sheet Bulk Metal Forming (published online 05. November 2020), S. 286-306.
Beschreibung

In sheet-bulk metal forming (SBMF), locally varying high tensile and compressive loads occur during the forming process. A superposition of the load stresses with manufacturing related residual stresses in the subsurfaces can increase the fatigue of functionally relevant tool areas. The form grinding process, as one of the last and quality-determining manufacturing steps, can be used to adapt the subsurface properties specifically to the load scenarios and stress states during the forming process. Therefore, the aim of the subproject B8 - Grinding Strategies for Local and Stress Orientated Subsurface Modification of Sheet-Bulk Metal Forming Tools - of the TCRC73 is the process safe application of locally adapted residual stresses in order to increase the service life of the forming tool. For this goal, fundamental relationships between grinding with toric tools and the subsurface properties of forming tools were investigated. The residual stress state is significantly determined by the three process parameters grinding strategy, feed velocity and CBN grain size. An empirical model for the prediction of residual stresses was derived from the main influencing process parameters. Other process parameters, such as the depth of cut and the path distance, which decisively determine the contact surface, have a subordinate role in the formation of surface modifications. The process reliability of the grinding process depends on the wear behavior of the tools. Grinding tools with a large grain diameter show a favorable wear behavior. In addition, the dressing process of the tools has a significant influence on the wear behavior. Furthermore, the grinding process as one of the last process steps can be used to improve the adhesion of ceramic Physical Vapour Deposition (PVD) coatings by an optimized pre-treatment and thus to substitute an additional nitriding process.  

ISBN 978-3-030-61902-2
DOI 10.1007/978-3-030-61902-2_13