Origin of sample size effect: Stochastic dislocation formation in crystalline metals at small scales

نویسندگان

  • Guan-Rong Huang
  • J. C. Huang
  • W. Y. Tsai
چکیده

In crystalline metals at small scales, the dislocation density will be increased by stochastic events of dislocation network, leading to a universal power law for various material structures. In this work, we develop a model obeyed by a probability distribution of dislocation density to describe the dislocation formation in terms of a chain reaction. The leading order terms of steady-state of probability distribution gives physical and quantitative insight to the scaling exponent n values in the power law of sample size effect. This approach is found to be consistent with experimental n values in a wide range.

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عنوان ژورنال:

دوره 6  شماره 

صفحات  -

تاریخ انتشار 2016