Structural and microstructural characterization of SiB0.5C1.5N0.8Al0.3 powders prepared by mechanical alloying using aluminum nitride as aluminum source

SiB0.5C1.5N0.8Al0.3 powders were fabricated by mechanical alloying using crystalline silicon (c-Si), hexagonal boron nitride (h-BN), graphite (C) and aluminum nitride (AlN) powders as starting materials. The microstructure of the synthesized SiB0.5C1.5N0.8Al0.3 powders is predominantly amorphous with a very small volume fraction of AlN nano-crystalline phase. The SiB0.5C1.5N0.8Al0.3 powders appeared to possess a structure containing hybridization of several bonds such as Si–C, B–C–N, C–C, B–N and Al–N because of the solid reactions among c-Si, h-BN, graphite and AlN. 29Si and 27Al solid-state nuclear magnetic resonance spectra showed the formation of amorphous SiC structure based on SiC4 sites and the coexistence of AlN4 and AlN5 units in SiB0.5C1.5N0.8Al0.3 powders, respectively.