Bai Y

Grasso S

Jayaseelan DD

Lee WE

Pramana S

Reece MJ

Skinner S

Single-phase Hf2Al4C5 ternary carbide was fabricated from Hf/Al/C powder mixtures by pressure assisted sintering techniques such as hot pressing and spark plasma sintering at 1900\ub0C for 3h and 10min, respectively. XRD confirmed that the ternary carbide started to form at temperatures as low as 1500\ub0C and with total formation of Hf2Al4C5 after reactive sintering for 1h at 1900\ub0C. It is evident from HRTEM that two Hf-C layers were sandwiched with 4 Al-C layers (Al4C3) in the Hf2Al4C5 ternary carbide. Tight interlocking of grains, faceted grains and stacking faults were occasionally observed. Thermal conductivity of Hf2Al4C5 is measured to be 14 w.m-1 k - 1 from room temperature to 1300\ub0C. The oxidation studies carried out at 1300\ub0C for 3h reveal that the oxidation layer thickness is around 220 μm and it contains microcracks closer to sample surface whereas the interface looks seamless without any cracking or spallation of the oxide layer

Fabrication and characterisation of single-phase Hf<sub>2</sub>Al<sub>4</sub>C<sub>5</sub> ceramics

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