Layer adhesion and critical strain of HFCVD diamond coatings on WC-Co substrate

Layer adhesion and critical strain of HFCVD diamond coatings on WC-Co substrate

LECHNER Stefan, BARON Sarah, HÖFER Markus, STEIN Christian, MÜLLER Sören

download PDF

Abstract. The extrusion of products with high demands on dimensional accuracy and surface quality, such as aluminum power bonding wires or bioabsorbable stents made of magnesium, renders high requirements on the extrusion die. With the application of HFCVD (Hot Filament Chemical Vapor Deposition) diamond coatings on cobalt-based tungsten carbide alloys, a die material with great hot strength, high surface hardness and low chemical adhesion could be provided. To identify WC-Co alloys with suitable cobalt content both for use as extrusion die and for coating with CVD diamond, investigations on ductility and hot strength as well as layer adhesion and interface stability were carried out. The mechanical properties of four WC-Co alloys containing 6 %, 9 %, 10 % and 12 % cobalt were determined by means of hot compression tests. Layer adhesion was evaluated by a standardized sandblasting test. Subsequently, hot compression tests were carried out with coated specimens to determine the critical deformation of the applied CVD diamond coatings.

Compression Tests, Cobalt Content, Mechanical Properties, Interface Stability

Published online 4/24/2024, 8 pages
Copyright © 2024 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: LECHNER Stefan, BARON Sarah, HÖFER Markus, STEIN Christian, MÜLLER Sören, Layer adhesion and critical strain of HFCVD diamond coatings on WC-Co substrate, Materials Research Proceedings, Vol. 41, pp 670-677, 2024


The article was published as article 74 of the book Material Forming

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

[1] M. Bauser, G. Sauer, K. Siegert, Strangpressen: Aluminium Fachbuchreihe, Aluminium-Verlag, Düsseldorf, 2001. ISBN 3410221816
[2] H.J. Weintraud, Neue Werkstoffe für Strangpressmatrizen, in: J. Baumgarten (Ed.), Strangpressen, DGM-Informationsgesellschaft m.b.H., Oberursel, 1989. ISBN 3-88355-160-0
[3] Upadhyaya, G.S., Cemented Tungsten Carbides – Production, Properties, and Testing, William Andrew, Norwich, 1998. ISBN 978-0-8155-1417-6.
[4] A.G. Guy, G. Petzow, Metallkunde für Ingenieure, in R. Sewig, D. Roess (Eds.), Technisch-Physikalische Sammlung Band 7, Akademische Verlagsgesellschaft, Frankfurt am Main, 1970.
[5] P. Kazanowski, A Study of Multi-material Die Insert Failure Mechanism in Aluminum Extrusion, Conf. 10th International Aluminium Extrusion Technology Seminar ET (2012), Miami.
[6] M.P. Clode, T. Sheppard, Formation of die lines during extrusion of AA6063, Mater. Sci. Technol., 6(8) (1990), 755–763.
[7] K. Müller, Grundlagen des Strangpressens: Verfahren, Anlagen, Werkstoffe, Werkzeuge, expert verlag, Renningen, 2003. ISBN 3-81692-018-7
[8] A.K. Chattopadhyay, P. Roy, A. Gosch, S.K. Sarangi, Wettability and machinability study of pure aluminium towards uncoated and coated carbide cutting tool inserts, Surf. Coat. Technol. 203 (2009), 954-951.
[9] S. A. Linnik, A. V. Gaidaichuk, and V. V. Okhotnikov, Influence of Cobalt on the Adhesion Strength of Polycrystalline Diamond Coatings on WC–Co Hard Alloys, Technical Physics, 63(2) (2018), 206–210,
[11] A.V. Shatov, S.S. Ponomarev, S.A. Firstov, Fracture and Strength of Hard metals at Room Temperature, in: V.K. Sarin (Ed.), Comprehensive Hard Metals, Elsevier, 2014, pp. 301-343.
[12] P. Ettmayer, Hardmetals and Cermets, Annu. Rev. Mater. Sci. 19:1 (1989), 145-164.
[13] EXTRAMET AG, Delivery Program 09/2022, Plaffeien, 2022.