کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1449956 | 988718 | 2007 | 9 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: A half-space Peierls–Nabarro model and the mobility of screw dislocations in a thin film A half-space Peierls–Nabarro model and the mobility of screw dislocations in a thin film](/preview/png/1449956.png)
In this paper, a half-space Peierls–Nabarro (HSPN) model is proposed to re-examine the mobility of a screw dislocation along a thin film/substrate (half-space) interface. In this configuration, the screw dislocation is subjected to an image force due to the free surface, and we are concerned with the interaction between the dislocation and the free surface. Unlike the original Peierls–Nabarro (P–N) model, the HSPN model takes into account the effect of the image force, which leads to modifications on analytical expression of the Peierls barrier stress. The modified Peierls stress is a function of the thin film thickness, which allows us to accurately predict the mobility of a dislocation in the interface between the thin film and the substrate. Based on the proposed HSPN model, we have found that the Peierls stress of a surface screw dislocation may be about 5–15% less than that in bulk materials.
Journal: Acta Materialia - Volume 55, Issue 6, April 2007, Pages 2149–2157