Preparation of polymer-derived Si–B–C–N monoliths by spark plasma sintering technique

Mirna Chaker Bechelany (1, 2) , Chrystelle Salameh (2) , Antoine Viard (2) , Lise Guichaoua (1) , Fabrice Rossignol (1) , Thierry Chartier (1) , Samuel Bernard (2) , Philippe Miele (2)

1 SPCTS-AXE1 - Axe 1 : procédés céramiques
2 IEM - Institut Européen des membranes

The present paper reports the preparation of sintering additive-free Si–B–C–N monoliths by spark plasma sintering (SPS) under nitrogen of polymer-derived Si–B–C–N powders. Powders are synthesized in nitrogen or ammonia atmosphere to modify their carbon content. The nitrogen-treated powders sintered in the temperature range 1500–1900 °C lead to monoliths with a density increasing from 2.4 to 2.6 g/cm3, Vickers harness and Young's modulus ranging from 0.7 to 5.4 GPa and 48 to 102 GPa, respectively. SiC was the first phase to nucleate around 1700 °C, whereas Si3N4 grew at 1800 °C. At this temperature, monoliths are pure electrical conductor nanocomposites mainly composed of Si3N4 and SiC nanophases embedded in a turbostratic BN(C) matrix. Above 1800 °C, Si3N4 was not identified. In comparison, ammonia-treated powders sintered at 1800 °C represent dense insulator composites mainly composed of Si3N4 and BN with a Vickers hardness as high as 15 GPa and an excellent stability in air.

Mots clés: Polymer-derived ceramics; (Nano)composites; Properties; Si–B–C–N; Spark plasma sintering

Domaines: Chimie; Matériaux

Mirna Chaker Bechelany, Chrystelle Salameh, Antoine Viard, Lise Guichaoua, Fabrice Rossignol, et al.. Preparation of polymer-derived Si–B–C–N monoliths by spark plasma sintering technique. Journal of the European Ceramic Society, 2015, 35 (5), pp.1361-1374. ⟨10.1016/j.jeurceramsoc.2014.11.021⟩. ⟨hal-01115389⟩