INVESTIGATION OF THE MECHANICAL TWINNING OF ANTIMONY SINGLE CRYSTALS BY NANOINDENTATIONO. M. Ostrikova and S. N. Dubb UDC 548.24 The twinning of antimony single crystals in nanoindentation has been investigated. The role of twinning in the formation of the impression of the Berkovich pyramid on the surface (111) of antimony single crystals has been established. A new method of investigation of the mechanical twinning of single crystals has been developed. For the first time, the duration of the process of twinning has been determined experimentally by a direct technique. aP. O. Sukhoi Gomel' State Technical University, Gomel', Belarus; bInstitute of Superhard Materials, National Academy of Sciences of Ukraine, Kiev, Ukraine. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 76, No. 1, pp. 170-172, January-February, 2003. Original article submitted November 5, 2001; revision submitted April 3, 2002.