Abstract

B4C is an important non-metallic material with extreme hardness. Its unique properties such as its hardness, good chemical resistance, low density (2.52 g/cm3), and neutron absorption properties make B4C an important material in a variety of technical applications. These include the machining of diamond tools, the creation of hot-pressed shot blast nozzles, ceramic tooling dies, armors, and shielding, control rod, and shut down pellets in nuclear power plants. However it is difficult to process B4C because achieving high density B4C components has been a challenge. In the prior work, Ni-B has been successfully coated onto individual B4C particle. The coating is controlled at nanometer thick and the thickness is adjustable. The effects of the amounts of the activation agent (PdCl2), and the complexing agent (C2H8N2) are one focus of this study. The addition rate of the reducing agent (NaBH4) has also been studied. SEM and XPS are employed to characterize the coated B4C surfaces. The Ni-B nanolayer formation is strongly dependent on the activation sites and the rate that NiP0P can be reduced. Fundamental Ni-B coating processes and morphological changes on the B4C particle surfaces are analyzed. Combustion driven compaction is used to produce high density B4C compacts from Ni-B nanolayer coated B4C particles.

 

Biography

Xiaojing Zhu received her B.S. from the department of chemical engineering, Tianjin University, China. Before she joined Virginia Tech in 2005, she got her master degree from the department of chemical engineering, University of South Carolina. She is currently a Ph.D. candidate under the direction of Dr. Kathy Lu. Her thesis focuses on the processibility of nickel nanolayer coated boron carbide.