Bulk boron carbide nanostructured ceramics by reactive spark plasma sintering

Bulk boron carbide (B4C) ceramics was fabricated from a boron and carbon mixture by use of one-step reactive spark plasma sintering (RSPS). It was also demonstrated that preliminary high-energy ball milling (HEBM) of the B+C powder mixture leads to the formation of B/C composite particles with enhanced reactivity. Using these reactive composites in RSPS permits tuning of synthesized B4C ceramic microstructure. Optimization of HEBM + RSPS conditions allows rapid (less than 30 min of SPS) fabrication of B4C ceramics with porosity less than 2%, hardness of similar to 35 GPa and fracture toughness of 4.5 MPa m (1/2)