Deposition of Nanoscopically Smooth DLC Tool Coatings for Dry Forming of Aluminum Sheets

Tim Abraham,Felix Flegler,Ingmar Bialuch,Günter Bräuer,Peter Groche

doi:10.1007/s11837-020-04174-9

Tim Abraham, Felix Flegler + Show 3 more

Open Access

https://doi.org/10.1007/s11837-020-04174-9

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Abstract

Recent investigations demonstrated the applicability of diamond-like carbon (DLC)-coated tools for dry forming of aluminum, which is a challenging application field due to the high adhesion tendency of aluminum. An exceptionally low roughness of the coated forming tool is required to prevent adhesion-induced tool failure. To establish dry forming of aluminum in industrial production processes, efficient methods must be developed to manufacture DLC-coated forming tools with reproducible high surface quality. This paper illustrates two DLC coating processes that are especially optimized for deposition of nanoscopically smooth DLC tool coatings. Two optimized coating systems were deposited, characterized, and subsequently evaluated using application-oriented strip drawing tests to validate their performance in comparison with a state-of-the-art coating system. One coating process showed high potential for production of DLC-coated forming tools with the required surface quality.

Highlights

The application fields of aluminum are continuously widening due to an ongoing trend towards lightweight construction
Recent investigations demonstrated the applicability of diamond-like carbon (DLC)-coated tools for dry forming of aluminum, which is a challenging application field due to the high adhesion tendency of aluminum
To establish dry forming of aluminum in industrial production processes, efficient methods must be developed to manufacture DLC-coated forming tools with reproducible high surface quality

Summary

INTRODUCTION

The application fields of aluminum are continuously widening due to an ongoing trend towards lightweight construction. As part of the posttreatment process, plasma etching allows selective removal of the coating material, offering the opportunity to adjust the surface roughness.[10,11] the second method aims to directly deposit nanoscopically smooth a-C:H coatings on tools.[12,13] The complete coating architecture and deposition parameters are changed to avoid formation of nanoscopic asperities as a result of the coating growth process Using these methods, test samples for tribological tests were coated and tested under application-oriented conditions to evaluate their potential to enable dry aluminum sheet forming more effectively

EXPERIMENTAL PROCEDURES

RESULTS AND DISCUSSION

CONCLUSION