Hardness to toughness relationship on WC-Co tool gradient materials evaluated by Palmqvist method

• Autorzy: Dobrzański L. , Dołżańska B.
• Języki publikacji: EN

Abstrakty

EN

Purpose: Goal of this work was to describe the propagation characteristic of cracks produced at the corners of Vickers indent and the toughness change in functionally graded WC-Co cemented carbide with high disproportion of cobalt matrix portion between core and surface layer. Design/methodology/approach: Investigations of toughness methods were developed during the investigations for tungsten carbide and cobalt, making it possible to obtain four materials and then their structure was determined. Findings: A wide variation in hardness and toughness has been obtained in WC-Co composites. The propagation characteristic of cracks produced at the corners of Vickers indent and the toughness change in functionally graded WC-Co cemented carbide with dual phase structure were investigated. It is shown that cracks tend to propagate both around and across WC crystal grain. The changes of toughness with the microstructure and an integrated strengthening effect, as well as high toughness characteristic of the tool gradient material are revealed. Practical implications: Material presented in this paper are characterized by very high hardness of the surface and relative ductility of core. The cobalt phase in obtained TGM material will changing smoothly. Originality/value: The Palmqvist test provides a useful method of measuring fracture toughness of material characterized by very high hardness of the surface and relative ductility of core.

Słowa kluczowe

EN

toughness; cemented carbides; Palmqvist; powder metallurgy

PL

kruchość; węgliki spiekane; Palmqvist; metalurgia proszków

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2010
• Tom: Vol. 43, nr 2
• Strony: 87--93
• Opis fizyczny: Bibliogr. 23 poz.

Twórcy

autor

Dobrzański L.

autor

Dołżańska B.

• Division of Materials Processing Technology, Management and Computer Techniques in Materials Science, Institute of Engineering Materials and Biomaterials, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland,

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