Design of ultra-high temperature ceramic nano-composites from multi-scale length microstructure approach. (1st December 2021)

• Record Type: Journal Article
• Authors: Gilli, Nicola; Watts, Jeremy; Fahrenholtz, William G.; Sciti, Diletta; Silvestroni, Laura
• Is Part Of: Composites. Number 226(2021)
• Publication Date: 2021-12-01
• Subjects: Nano-structures -- Core-shell -- Interface/interphase -- Electron microscopy -- Sintering; Composite materials -- Periodicals; Materials science -- Periodicals; Composite materials; Periodicals; Electronic journals; 620.118
• DOI: 10.1016/j.compositesb.2021.109344
• Languages: English
• ISSNs: 1359-8368

Abstract

Abstract: The evolution of the multi-scale microstructure of a (Zr, Ta)B2 solid solution was studied as a function of time and temperature. The ceramics were produced by hot pressing a mixture of ZrB2 with 15 vol% TaSi2 followed by annealing at 2100 °C. Formation of a super-saturated solid solution led to the precipitation of TaC nano-needles within the micron-sized boride grain matrix. Phase stability diagrams were used to define the conditions of partial pressure within the sintering chamber that drove precipitation of nano-inclusions in the form of either metal or carbide. Through this approach, other systems containing various transition metals were explored to design other formulations for in-situ nano-composites with unprecedented strength at ultra-elevated temperatures. Graphical abstract: Image 1