Estimation of Dislocation Concentration in Plastically Deformed FeCrNi Alloy by Positron Annihilation Lifetime

Abstract:

Dislocations would be induced after plastic deformation, which might change the mechanical properties of solids. FeCrNi austenitic model alloy and its Mo-diluted alloy were cold rolled with different degree of thickness reduction. Positrons are sensitive to point defects, which are easily trapped and annihilated around the trapping sites. The mean positron lifetimes have been used to estimate the average dislocation concentration in solids. Meanwhile, the trapping efficiency μ was calculated from the lifetime results. The trapping efficiency value is estimated about 3.31×10^-7 cm³s^-1 for FeCrNi alloy and 3.31×10^-7 cm³s^-1 for Mo-diluted alloy, respectively. The increment of the hardness value during plastic deformation is related to the increase of the dislocation density and dislocation pile up in solids.

• Periodical: Defect and Diffusion Forum (Volume 373)
• Pages: 162-166
• DOI: https://doi.org/10.4028/www.scientific.net/DDF.373.162
• Online since: March 2017
• Authors: Er Yang Lu, Xing Zhong Cao, Shuo Xue Jin, Yi Hao Gong, Peng Zhang, Run Sheng Yu, Bao Yi Wang*
• Keywords: Dislocation Concentration, FeCrNi Alloy, Plastic Deformation, Positron Annihilation

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