Advisor: Bai Cui Molybdenum aluminum boride (MoAlB) is a ternary transition metal boride which has promising aeronautic and nuclear applications. It inheres excellent properties of the binary transitional metal borides (e.g., MoB, ZrB2) such as high melting temperature, high hardness, and thermal conductivity. Besides, MoAlB is superior to MoB because: (1) the Al element provides an oxidation r...

In the frame of Horizon 2020 European C3HARME research project, manufacture ZrB2-based CMCs was developed through different processes: slurry infiltration and sintering, radio frequency chemical vapour (RF-CVI) reactive metal (RMI). To assess high temperature stability, room bending strength measured after oxidizing samples at 2278 K compared to as-produced materials. Microstructures were analy...

NiAl composite coating strengthened by ZrC and ZrB2 phases is synthesized the plasma cladding process. The influence of speed on microstructrue properties coatings studied. main are NiAl, γ-(Fe,Ni), phases. in shape points small blocks, shows long strips needle bar. slower speed, larger size reinforcing With increase wear resistance improves. Coating with 10mm/s has excellent wear-resistance pr...

Hypersonic flights, re-entry vehicles, and propulsion applications all require new materials that can perform in oxidizing or corrosive atmospheres at temperatures in excess of 2000°C and sometimes over the course of a long working life. Ultra High Temperature Ceramics (UHTCs) are good candidates to fulfill these requirements. Within this family, the ZrB2 and HfB2 based composites are the most ...

A combination of ab initio, atomistic and finite element methods (FEM) were used to investigate the structures, energetics and lattice thermal conductance of grain boundaries for the ultra high temperature ceramic ZrB2. Atomic models of idealized boundaries were relaxed using density functional theory. Information about bonding across the interfaces was determined from the electron localization...

The aim of this work is to optimize the oxidation resistance of ZrB2-SiC-based composites with different additives. Effect of nine factors including SiC, Cf, MoSi2, HfB2 and ZrC contents, milling time of Cf (M.t) and SPS parameters such as temperature, time and pressure on oxidation resistance in four levels was investigated. Taguchi design was applied to explore effective parameters for ...