B4C-(Hf,Zr,Ta,Nb,Ti)B2 composites prepared by reactive and non-reactive spark plasma sintering

Abstract

Based on the carbide boronizing reaction, B4C-(Hf,Zr,Ta,Nb,Ti)B2 composites were prepared by reactive and non-reactive spark plasma sintering using self-synthesized (Hf,Zr,Ta,Nb,Ti)C and compared with previously reported B4C-(Hf,Zr,Ta,Nb,Ti)B2 composites prepared by reactive spark plasma sintering using corresponding 5 commercial individual transition metal carbides. Irrespective of sintering methods, B4C-(Hf,Zr,Ta,Nb,Ti)B2 prepared by using the self-synthesized (Hf,Zr,Ta,Nb,Ti)C powder presented higher relative densities, smaller grain sizes, a more homogeneous elemental distribution and higher Vickers’ hardness than the materials available in the literature. However, compared with reactive spark plasma sintering, B4C-(Hf,Zr,Ta,Nb,Ti)B2 prepared by non-reactive spark plasma sintering had a more uniform phase distribution, leading to the higher Vickers hardness up to about 30 GPa.