LAUSR

Abstract In this work, highly pure Nb2AlC was successfully synthesized using the spark plasma sintering (SPS) technique with Nb, NbC and black carbon as raw materials at 1450 °C and 30 MPa for 8 min. The obtained Nb2AlC grain shows a characteristic layered structure. More interestingly, the obtained Nb2AlC exhibits good electrical, thermal and mechanical properties. The coefficient of thermal expansion is 9.0 × 10−6 K−1 from room temperature to 1200 °C. The electrical conductivity reaches 1.3 × 106 S m-1 at 500 °C, indicating excellent high-temperature conductivity. The Vickers hardness and flexural strength are 4.0 GPa and 440 ± 10 MPa, respectively. Importantly, fracture toughness of the obtained Nb2AlC material reaches 7.8 ± 0.2 MPa m1/2, which is higher than that of other previously studied MAX materials. Therefore, SPS is a very effective method to fabricate Nb2AlC materials and can also be used to prepare other MAX materials.