کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1448408 | 988672 | 2010 | 10 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Dependence of strain rate sensitivity upon deformed microstructures in nanocrystalline Cu Dependence of strain rate sensitivity upon deformed microstructures in nanocrystalline Cu](/preview/png/1448408.png)
The creep behavior of nanocrystalline copper was experimentally characterized with nanoindentation using two sequential regimes, i.e., loading and holding. Significantly enhanced strain rate sensitivity was found within an unusually narrow range of creep rate in the holding regime, which is attributed to the deformed microstructure generated during the loading regime. By quantitatively analyzing the creep rate and rate sensitivity exponent of NC Cu in the holding regime, both the grain boundary sliding (GBS) and dislocation activities are found to be responsible for the observed abnormal behavior, with the contribution of GBS decreasing with increasing grain size and increasing with decreasing loading strain rate. These findings provide a potential way of adjusting the mechanical properties of nanocrystalline metals by pre-straining.
Journal: Acta Materialia - Volume 58, Issue 15, September 2010, Pages 5196–5205