Fabrication and characteristics of TiB2/Al2O3 core/shell particles by hybridization

Microhybridization as a surface modification method was used to prepare TiB2/Al2O3 core/shell particles in this paper. The experiment included two parts. One part was that TiB2 (micron)/Al2O3 (nano) core/shell particles were fabricated directly by hybridization. Another part was that TiB2 (micron)/Al2O3 (sub-micron) composite particles were prepared using PE-wax as a transition layer, which has good binding capacity for both of them. PE-wax particles were first coated onto TiB2 particles by hybridization, and then the sub-micron Al2O3 particles were coated onto the surface of TiB2/PE-wax particles again. The coating process, effects of the transition layer and the structure of core/shell particles were investigated. The core/shell particle features were characterized by SEM, TEM, EDS, XPS and XRD. Results showed that after hybridization nano-Al2O3 particles were coated directly on the surface of TiB2 particles, but the sub-micron Al2O3 could not. When adding PE-wax as a transition layer, PE-wax was filmed on the surface of TiB2 particles and the sub-micron Al2O3 particles were coated successfully on the surface of TiB2/PE-wax particles by hybridization. The PE-wax transition layer plays a role of binder in forming TiB2(PE-wax)/Al2O3 core/shell particles.