Interface Reactivity and Induced Phenomena during Sintering in a Model Steel/Cemented Carbide Bimaterial

• Published in: Advanced engineering materials 2011-07, Vol.13 (7), p.594-598
• Main Authors: Thomazic, Aurélie, Pascal, Céline, Chaix, Jean-Marc
• Format: Article
• Language: English
• Subjects: Binders; Carbides; Cemented carbides; Chemical Sciences; Ferrous alloys; Iron; Material chemistry; Sintering; Steel making; Steels
• ISSN: 1438-1656; 1527-2648; 1527-2648
• DOI: 10.1002/adem.201000343

Direct elaboration of a WC base cemented carbide/Fe base alloy model bimaterial by cosintering is studied. In this material, dramatic changes are observed for small modifications of the sintering temperature (20 °C) or the composition of the Fe base (+/− 0.1% C): overall shrinkage, macroscopic deformations, and binder fraction of the carbide material. This paper shows how these phenomena originate at the interface and then propagate inside the bulk. This example illustrates the need for taking into account chemical interaction at interfaces during cosintering of multimaterials, as these regions are thermodynamically far from equilibrium. During sintering of bimaterials, the interface region is thermodynamically far from equilibrium. An accurate knowledge and control of chemical interactions is therefore required, since diffusion, phase formation, etc. occur and influence the sintering of the bulks far from interface. This is illustrated in the case of a WC base cemented carbide/Fe–W–C steel model bimaterial, in which uncontrolled interface phenomena can induce second phase carbide formation at the interface, and liquid migration and macroscopic changes in the sample.