Influence of nitrogen Gas pressure on the miscibility Gap in the Ti-Zr carbonitride system
2012 (English)In: International Journal of Refractory Metals and Hard Materials, ISSN 0263-4368, Vol. 32, 11-15 p.Article in journal (Refereed) Published
The microstructure of cemented carbides with a gradient structure at the surface consists of WC, cubic carbonitrides and a binder phase. The carbonitrides can, for example, consist of Ti(C,N)-Zr(C,N) where it is reasonable to believe that there is a miscibility gap with Ti-rich and Zr-rich carbonitrides. In the present work, the effect of the N-2-gas pressure on the equilibrium composition of the miscibility gap in the (Ti,Zr)(C,N) system has been investigated. In the study, the carbonitride system is in equilibrium with: WC, liquid binder, graphite and, N-2-gas of different pressures. Both Fe and Co are used as binder phase to study the effect of the binder phase. The results verify that there is a miscibility gap in the carbonitride system and that the region of the miscibility gap will change when N is introduced. There is a critical N-2-gas pressure lower than 0.1 bar and above that pressure the compositions of the carbonitride are rather constant as a result of the formation of a surface rim.
Place, publisher, year, edition, pages
2012. Vol. 32, 11-15 p.
Cemented carbides, TiC, ZrC, Miscibility gap
Metallurgy and Metallic Materials
IdentifiersURN: urn:nbn:se:kth:diva-95088DOI: 10.1016/j.ijrmhm.2011.12.014ISI: 000302841400003ScopusID: 2-s2.0-84858336869OAI: oai:DiVA.org:kth-95088DiVA: diva2:527701
QC 201205222012-05-222012-05-142013-11-18Bibliographically approved