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. Access through your institution Buy or subscribe This is a preview of subscription content,

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DECORATION OF GRAIN BOUNDARIES BY INTERSTITIAL SOLUTES Article Open access 15 June 2023 REFERENCES * Dubrovinskaia, N. & Dubrovinsky, L. Controversy about ultrahard nanotwinned cBN.

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Download references AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, 066004, China Yongjun

Tian, Bo Xu, Dongli Yu, Wentao Hu, Yufei Gao, Kun Luo, Zhisheng Zhao, Li-Min Wang, Bin Wen, Julong He & Zhongyuan Liu * State Key Laboratory for Superhard Materials, Jilin University,

Changchun, 130012, China Yanming Ma * Center for Advanced Radiation Sources, University of Chicago, Chicago, 60439, Illinois, USA Yanbin Wang * TEM Laboratory, University of New Mexico,

Albuquerque, 87131, New Mexico, USA Yingbing Jiang * School of Material Science and Engineering, Hebei University of Technology, Tianjin 300130, China, Chengchun Tang Authors * Yongjun Tian

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