Influence of Dislocation Density on Micromechanical Characteristics of Cu₆Sn₅ and Cu₃Sn

Abstract:

The influence of dislocation density on micromechanical characteristics of Cu₆Sn₅ and Cu₃Sn was studied by nanoindentation. The dislocation density dependent hardness of Cu₆Sn₅ and Cu₃Sn was quantitative analyzed. High dislocation density increased the critical shear stress corresponding to the first pop-in events and induced micro plastic deformation before the first pop-in events. For Cu₆Sn₅, dislocation creep and lattice diffusion dominate the high stress regime (HSR) and the low stress regime (LSR), respectively, regardless of the dislocation density. High dislocation density increases the stress exponent (n) of HSR, but decrease n of LSR. Dislocation motion is the dominate creep mechanism of unstrained Cu₃Sn. After pre strain, the creep behavior of Cu₃Sn was divided into HSR and LSR. But dislocation motion is still the dominate creep mechanism. Potential mechanism of the dislocation density dependent micromechanical characteristics was explained based on our experimental results.

• Periodical: Materials Science Forum (Volume 815)
• Pages: 115-124
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.815.115
• Online since: March 2015
• Authors: Yi Kai Wang*, Wen Sheng Liu, Yun Zhu Ma, Yu Feng Huang, Ya Tang
• Keywords: Cu3Sn, Cu6Sn5, Dislocation Density, Micromechanical, Nanoindentation

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