Preparation of Al₂0₃/ZrB₂ Composites by Reactive HIP sintering

Abstract

A mixed powder of Al, Zr, B₂O₃ of 2:1:1 mole ratios was prepared by ball milling. The glass capsule filled with the mixed powder was HIP’ ed under the condition of 1500°C, 100 MPa and 1 h. The HIP-sintered product was made of Al₂O₃ and ZrO₂ which formed in HIP’ ing by reaction (1).
2Al + Zr + B₂O₃ =Al₂O₃ + ZrB₂ (1)
When overmilling has been done, the reaction (1) occurred suddenly mechanochemically to form the mixed powder of Al₂O₃ and ZrO₂. The mechanochemical powder did not sinter well under the same HIP condition.