Microstructure and Mechanical Properties of ZrB2–HfC Ceramics Influenced by HfC Addition

摘要: ZrB2–HfC ceramics have been fabricated using the liquid phase sintering technique at a temperature as low 1750 °C through addition of Ni. The effects HfC on microstructure and mechanical properties ZrB2–based investigated. These were composed ZrB2, HfC, Ni, small amount possible (Zr, Hf)B2 solid solution. Small grains distributed among ZrB2 grain boundaries. could improve density play pinning role. With content increasing from 10 wt % to 30 %, more boundaries, leading weaker interface bonding grains; relative Vickers hardness increased, flexural strength fracture toughness decreased. weak for 20 contents was main cause decrease in both toughness.