Carbide/binder interfaces in Ti(CN)–(Ti,W)C/(Ti,W)(CN)-based cermets

Author:

Park, Choongkwon   Nam, Sangwoo   Kang, Shinhoo  

Journal:

Journal of Alloys and Compounds

Issue Date:

2016

Abstract(summary):

Highlights

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The addition of (Ti_0.88W_0.12)C significantly improved the toughness of cermets.

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The ceramic particles in the cermets exhibited {111} plane faceting.

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The coherency state at the core/rim/binder interfaces led to high toughness.

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The thermal stability of constituents and nitrogen in the system are the main causes.

Abstract

Partially solutionized carbide cermets (PSCs) were prepared for cutting tool applications by replacing a portion of Ti(CN) with (Ti_0.88W_0.12)C or (Ti_0.88W_0.12)(C_0.7N_0.3) in a conventional Ti(CN)-based cermet. The PSC containing (Ti_0.88W_0.12)C exhibited high fracture toughness with no loss of hardness. The elimination of Ti(C_0.7N_0.3) cores in the microstructure reduced the strain at the core/rim interfaces, leading to the increase in fracture toughness. The PSC containing (Ti_0.88W_0.12)C showed coherent relationships at the core/rim and rim/binder interfaces, contributing to the improved mechanical properties. In contrast, nitrogen in (Ti_0.88W_0.12)(C_0.7N_0.3) resulted in a different microstructure and properties. The major factors determining the mechanical properties of the cermets are discussed in terms of the carbide/binder interfaces and the thermal stability of the added carbides.

Graphical abstract

Page:

671-677