Tribological studies on multi-coated forming tools

Weikert, T.1, a; Tremmel, S.1, b; Stangier, D.2, c; Tillmann, W.2, d; Krebs, E.3, e; Biermann, D.3, f

Lehrstuhl für Konstruktionstechnik KTmfk, Martensstraße 9, 91058 Erlangen
Institute of Materials Engineering LWT, TU Dortmund, Leonhard-Euler-Str. 2, D-44227 Dortmund, Germany
Institute of Machining Technology, TU Dortmund University, Baroper Str. 303, D-44227 Dortmund, Germany

a); b); c)>; d); e); f)


Processes of Sheet-Bulk Metal Forming combine operations of both sheet and bulk metal forming, enabling the production of closely-toleranced functional components. Locally differing friction conditions on a single tool surface are crucial to control the material flow and to reduce process forces and tool wear. In order to understand how different friction conditions on a multi-coated tool surface affect the material flow during forming operations, variants of amorphous carbon coatings (a-C:H:W) and Cr-based hard coatings (CrAlN, CrAlCN) were deposited in combinations side by side on punches of ring compression tests. Evaluating the rings’ shapes revealed the coatings’ effects on material flow in terms of ring inner contours with sections of varying curvatures. Characteristic friction mechanisms were observed, which allowed a local delimitation of friction conditions by selectively applied coatings.


Sheet-bulk metal forming; Tailored surfaces; Cr-based hard coatings; Amorphous carbon coatings


Journal of Manufacturing Processes, 49 (2020), pp. 141-152, ISSN 1526-6125 , doi: 10.1016/j.jmapro.2019.11.021