SiC-Based Ceramics from Naturally-Derived Scaffolds Katherine T. Faber, Northwestern University, DMR 0244258

1. SiC-Based Ceramics from Naturally-Derived ScaffoldsKatherine T. Faber, Northwestern University, DMR 0244258 Al-Si-Mg alloy Biomorphic silicon carbide (bioSiC) is produced by the controlled pyrolysis of wood to provide a carbon scaffold for infiltration by liquid silicon. Silicon reacts with carbon to form silicon carbide. The resulting microstructures are complex honeycomb-like structures. SiC/Al composites can be produced by infiltrating the SiC honeycombs with a molten aluminum alloy. The alloy imparts significant toughening to the composite, as shown at right. Even at 500°C, when the alloy is nearly molten, crack bridging by the alloy (seen in the micrographs below), is effective at doubling the fracture toughness of the SiC scaffold. This work is performed in conjunction with researchers at the University of Seville and the Polytechnic University of Madrid. Beech-derived composite Porous beech-derived SiC 10 μm 25ºC 500ºC

2. SiC-Based Ceramics from Naturally-Derived Scaffolds:The Materials World NetworkKatherine T. Faber, Northwestern University, DMR 0244258 Rich collaborations established in the Materials World Network Program enhance both the pace and the value of research. Thomas Wilkes (shown at right, in Cordoba) made key high temperature mechanical property measurements at the Polytechnic University of Madrid under the guidance of Professor Javier LLorca. P.I. Katherine Faber recapped the collaborative work in seminars in Madrid and Seville, as noted in EL PAÍS, Spain’s largest circulation newspaper. Professor Julián Martinez Fernández of the University of Seville, likewise, shared the latest developments during a visit to the U.S.