Microstructure and thermal stability of amorphous SiBCNAl powders fabricated by mechanical alloying

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

“…The interplanar distance measured from the image is 0.250 AE 0.002 nm, which matches well with d (1 1 1) = 0.251 nm of b-SiC (3C) or d (0 0 2) = 0.251 nm of AlN. In view of previous studies which did not find the existence of b-SiC nano-crystalline under the similar milling conditions [7], the nano-crystalline phase in Fig. 2(b) can be identified as AlN crystalline.…”

“…It is shown that the diffraction peaks of AlN can still be observed after 30 h of milling. This indicates that amorphization of the powder mixture using AlN powder as aluminum source is more difficult than that of the sample using Al powder as aluminum source [7]. When the milling time is up to 60 h, the powders are still not completely amorphous with very small diffraction peaks of AlN.…”

“…The results revealed that the solid reactions among c-Si, h-BN, graphite and AlN occurred by MA, which resulted in the generation of new chemical bonds. Compared with the SiB 0.5 C 1.5 N 0.5 Al 0.3 powders prepared using Al powder as the source of aluminum [7], the SiB 0.5 C 1.5 N 0.8 Al 0.3 powders have similar bonding types but no oxygen-containing bonds. 29 Si and 27 Al solid-state NMR spectra of the SiB 0.5 C 1.5-N 0.8 Al 0.3 powders are shown in Fig.…”

“…The result indicates that the local environment around the aluminum atoms changes from AlN 4 to the mixture of AlN 4 and AlN 5 by mechanical alloying. As compared with the SiB 0.5 C 1.5 N 0.5 Al 0.3 powders prepared using Al powder as the source of aluminum [7], the …”

“…In our previous work, amorphous SiB 0.5 C 1.5 N 0.5 Al 0.3 powders have been fabricated by MA using c-Si, h-BN, graphite and aluminum (Al) powders as starting materials [7]. In order to further investigate the influence of different aluminum source on the microstructure and structure of SiBCNAl powders, we prepared SiB 0.5 C 1.5 N 0.8 Al 0.3 powders using AlN powder as the source of aluminum in this paper for the first time.…”