COMPARISON OF USING NANOSIZE AND MICRONIZE TIB POWDER ON MECHANICAL AND MICROSTRUCTURAL PROPERTIES OF BC-TiB COMPOSITES

Due to their outstanding properties such as high hardness, low density, high refractoriness, and high neutron absorption cross-section, B4C ceramics are regarded as strategic materials in military industrial applications as armors and neutron absorbent in nuclear industries. The effect of using nanosize and micronize TiB2 powder as secondary phase on sintering behavior and mechanical properties in BC-TiB2 composites was investigated. Different amounts of micronize and nanosize TiB, powder, mainly 0 to 30 wit% were added to the base material. Pressureless sintering was conducted at 1950, 2050 and 2150C, therefore mechanical and microstructural properties were compared. It is obvious that higher relative density, flextural strength, fracture toughness and microstructural uniformity are attributed to using nanosize TiB2 powder as secondary phase in BCnanoTiB2nanocomposite.

Keywords:

BC , TiB:Sintering temperature , Nanosize , Micronize