Affordable Access

Orientation-Independent Yield Stress and Activation Volume of Dislocation Nucleation in LiTaO3 Single Crystal by Nanoindentation

Authors
  • ma, yi
  • huang, xianwei
  • song, yuxuan
  • hang, wei
  • yuan, julong
  • zhang, taihua
Publication Date
Aug 30, 2019
Source
MDPI
Keywords
Language
English
License
Green
External links

Abstract

Relying on nanoindentation technology, we investigated the elastic-to-plastic transition via first pop-in event and estimated the corresponding shear stress for incipient plasticity, i.e., yielding in the three typical orientations, i.e., X-112&deg / , Y-36&deg / , and Y-42&deg / planes. The occurrence of incipient plasticity exhibited a stochastic distribution in a wide range for the three orientations. Accordingly, the obtained values of yield stress were uniform and scattered in the range from about 4 to 7 GPa for LiTaO3 single crystal. The orientation effect on yield stress at the nano-scale was revealed to be insignificant in LiTaO3 single crystal. The yield stresses were 5.44 &plusmn / 0.41, 5.74 &plusmn / 0.59, and 5.34 &plusmn / 0.525 GPa for the X-112&deg / , Y-36&deg / , and Y-42&deg / planes, respectively. The activation volumes of dislocation nucleation were computed based on the cumulative distribution of yield stress, which were 12 &Aring / 3, 8 &Aring / 3, and 9 &Aring / 3 for the X-112&deg / , Y-36&deg / , and Y-42&deg / planes. The results indicated that point-like defects could be the source of plastic initiation on the surface of LiTaO3 single crystal.

Report this publication

Statistics

Seen <100 times