Effect of Graphite Additions on the Properties of <TEX>$Ti(C_xN_{1-x})$</TEX> Ceramics

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J. Korean Ceram. Soc. > Volume 34(5); 1997 > Article

Journal of the Korean Ceramic Society 1997;34(5): 443.

Graphite 첨가에 따른 $Ti(C_xN_{1-x})$세라믹스의 물성

고준, 최영민¹, 이재도¹, 김종오

충남대학교 재료공학과
¹한국화학연구소 화학소재연구단

Effect of Graphite Additions on the Properties of $Ti(C_xN_{1-x})$ Ceramics

ABSTRACT

Titanium carbonitride (Ti(CxN1-x)) ceramics were prepared by hot pressing of the mixture of TiN and graphite. Hot pressing was performed in a graphite mold at 198$0^{circ}C$ for 40 min under 44 MPa in N2 atmosphere. The effect of graphite addition on sinterability and the mechanical properties of titanium carbonitride were investigated. In this study, the solubility limit of graphite in Ti(CxN1-x) was slightly below 10 wt% based on the results of XRD analysis. Within the solubility limit, graphite dissolved completely into titanium nitride and formed the single phase Ti(CxN1-x) solid solution. Peak relative density of 99% and hardness of 16 GPa were observed for Ti(CxN1-x) ceramics with 7 wt% graphite while maximum flexural strength of 500 MPa and fracture toughness of 4.0 MPa.m1/2 were observed for Ti(CxN1-x) ceramics with 10 wt% graphite. The electrical resistivities of the ceramics with 7 wt% and 10 wt% graphite were observed 40 {{{{ mu OMEGA }}cm and 50 {{{{ mu OMEGA }}cm respectively.

Key words: Titanium carbonitride, Graphite, Solid solution, flexural strength, Toughness, Electrical resistivity