Читать книгу Metal Oxide Nanocomposites - Группа авторов - Страница 40

In these composites, the boron is coated on the tungsten substrate. Borontungsten fibers are obtained when hot tungsten filament is allowed to pass through a mixture of gases and boron with certain thickness gets deposited on tungsten substrate. The thickness of tungsten remains constant in the process. The properties of boron fibers depend upon their diameter due to the changing ratio of boron and tungsten and also with the associated surface defects. The boron fiber possesses good stiffness and strength while their tensile modulus is ~5 times better that of glass fibers. The boron coated carbons fibers are quite cheaper than boron tungsten fiber, however, they suffer from low modulus of elasticity [6].