Tailored tool surfaces

Further qualification of machine hammer peening technology for industrial use (HaPTec – Hammer Peening Technology)

 

Motivation

In industrial production processes, tool surfaces are often exposed to high loads combined with highest expectations regarding their surface quality at the same time. These requirements are fulfilled by tool- and mold-making companies with high expenditure on technology and human resources during production, hardening and polishing of the tools. A possibility to shorten the process-chain during production is mechanical hammer peening (MHP).

In concluded research activities smoothing as well as hardening and close to surface compressive residual stresses were proved. These effects are already used in the automotive industry and the procedure is applied to process drawing molds. Thus, processing time can be reduced. Due to missing guidelines and uncertainty regarding the machineable materials the process has to face serious concerns before entering a broad industrial field of application. Processing of basic geometries and free-form-surfaces are state of the art in MHP while narrow radii, boreholes or even undercuts in tools cannot yet be treated specifically. This also is the challenging aspect for MHP to enter the sector of bulk metal forming, where for example extrusion tools have to be machined. Furthermore, MHP tools are only used on multi-axis machining centers. Experiences in the usage on industrial robots of small dimensions and low load capacity barely exist.

 
[1] Process characteristics Machine Hammer Peening
[1] Process characteristics Machine Hammer Peening
 

Objective

This project’s objective is the further qualification of the machine hammer peening process. The industrial appliers’ requirements have to be collected and evaluated and need to be considered during the design of a new hammering kinematic, which should make possible the processing and machining of boreholes, undercuts and narrow radii. Furthermore, a benchmark with other technologies of surface treatment is performed. The occurring surface-mechanisms must be investigated and additionally a material-catalogue has to be created. At the end of the project guidelines for an industrial application of machine hammer peening need to be established to promote a broad implementation of the MHP-technology.

 
[2] Challenges for Machine Hammer Peening
[2] Challenges for Machine Hammer Peening
 

Approach

The project is carried out in cooperation with the Institute for Applied Materials (IAM-WK) of the Karlsruhe Institute of Technology and the Institute for Production Engineering and Laser Technology (IFT) of the Vienna University of Technology within the CORNET program, founded by the European Commission. Initially, the demands of the industrial users are discussed and evaluated and a list of requirements is created concerning the hammering kinematic and further boundary conditions of the MHP-process. Then, a benchmark with competing systems and an analysis of the surface modification effects is conducted with the help of finite element analysis (FEA). In the further evolution of the project a hammering-kinematic is designed and built, which enables the processing of hardly accessible surface regions and a comprehensive material catalogue is created. Additionally, the system- and process-integration in existing process chains is investigated and guidelines for the application of MHP are established.

Acknowledgment

The PtU would like to thank the European Research Association for Sheet Metal Working (EFB) and the following companies for their support.

  • DAIMLER
  • KAMAX
  • LS MECHANIK
  • Accurapuls
  • ECOROLL
  • FILZEK TRIBOtech
  • 3S engineering
  • BAUBLIES
  • OSK Kiefer
  • WFL Millturn Technologies
  • nemak
  • VOITH
  • Modelshop Vienna
  • ENGEL
  • EW Ernst Wittner
  • FASCHANG Werkzeugbau
  • BEKUM