Formation Mechanisms of Ti3 SnC2 Nanolaminate Carbide Using Fe as Additive.

Reactive sintering of 3 Ti: Sn:2 C and 3Ti:Sn:2C:0.6Fe powder mixtures is studied in the temperature range 510°C-1200°C under argon. It is demonstrated that the recently discovered Ti₃ SnC₂ phase is formed, provided that Fe is added to a 3 Ti: Sn:2 C reactant mixture within the synthesis conditions used. Using dilatometric and X-Ray diffraction analyses, the formation mechanism of Ti₃ SnC₂ is discussed. Results show that at low temperature (about 510°C), tin is consumed to form Fe _x Sn _y intermetallics. At high temperature (about 1060°C), tin is newly available to form Ti₃ SnC₂ due to the melting of Fe _x Sn _y. Then, the intermediate phases, TiC and Ti₂ SnC, and/or Ti₅ Sn₃, TiC, C, and Ti are dissolved in the ( Fe + Sn) liquid phase and Ti₃ SnC₂ very likely precipitate from the melt. The second part of the study deals with the optimization of the Fe content in the initial 3Ti:Sn:2C reactant powder mixture to synthesize samples with larger Ti₃ SnC₂ content by hot isostatic pressing. [ABSTRACT FROM AUTHOR]