Optimization of tool use in sheet metal forming

The aim of the research project is to analyze and predict the development and phenomena of the advanced wear development as well as the tool failure in sheet metal forming. Particularly, the wear behavior in the transition from wear development from steady state to failure is being investigated (Figure 1). In addition, the factors that influence the tool wear are being researched. With these results, it will then be possible for better estimation of tool life in the future and better plan for maintenance intervals.

Motivation

The increasing use of higher and highest strength steels (AHSS) in sheet metal forming leads to new industrial challenges. One of the main problems is the high tribological load conditions during forming, which can lead to premature failure of the lubricating film and subsequent product failure. This leads further to failure of the forming tools. In order to meet this challenge, it is essential to extend the knowledge about tool life and wear development. An exact knowledge of the wear mechanisms and wear interactions allows an approximation of tool life and thus an optimized tool use. This has a significant potential for increasing economy, quality and process stability in the sheet metal forming industry. The reasons, which cause the development of wear and the failure of a tool, have not yet been sufficiently researched.

[1] Wear development of steel

Methodical approach

In the first phase of the project, the current measuring system of wear characterization is upgraded in order to obtain more measuring values describing the wear development. The main objective of the second project phases is to determine the factors influencing wear development. In this project, the hardness and the surface topography of the forming tool are selected as influencing factors. Finally, suitable measures to extend the life span of the forming tools are derived.

Acknowledgement

The Institute for Production Engineering and Forming Machines would like to thank the German Research Foundation (DFG) for their support in this project.

German Resear ch Foundation