Abstract
Arising from N. Dubrovinskaia & L. Dubrovinsky Nature502,http://dx.doi.org/10.1038/nature12620(2013)
Dubrovinskaia and Dubrovinsky1 question the sub-grain structure and ultrahigh hardness of our nanotwinned cubic boron nitride (nt-cBN; ref. 2), and make the following assertions: (1) hardening related to nanotwinning in cBN has been known for tens of years, (2) our X-ray diffraction (XRD) and Raman results do not show the signatures of nanotwinning, (3) there are large wurtzite-structure boron nitride (wBN) domains present in our samples, and (4) our hardness values are unconvincing. We argue below that all these claims are incorrect.
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References
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Tian, Y., Xu, B., Yu, D. et al. Tian et al. reply. Nature 502, E2–E3 (2013). https://doi.org/10.1038/nature12621
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DOI: https://doi.org/10.1038/nature12621
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