کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1581909 | 1514865 | 2008 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: The effect of geometrically necessary dislocations on grain refinement during severe plastic deformation and subsequent annealing of Al–7% Si The effect of geometrically necessary dislocations on grain refinement during severe plastic deformation and subsequent annealing of Al–7% Si](/preview/png/1581909.png)
A comparative study has been made of room temperature severe plastic deformation of an Al–7% Si composite, containing large Si particles, and a monolithic Al–0.5% Si with the same chemical composition as that of the composite matrix. In the composite, the large local strain gradients existing between the matrix and the coarse, undeformable, Si particles produce a much higher density of geometrically necessary dislocations which are responsible for much faster grain refinement. Annealing at 200 °C produces only small variations in grain size due to the precipitation of fine Si particles while severe deformation at the same temperature leads to a much larger grain size with much coarser precipitates. The corresponding mechanical properties have been analysed in terms of the different microstructural contributions to strengthening in both alloys.
Journal: Materials Science and Engineering: A - Volume 493, Issues 1–2, 15 October 2008, Pages 141–147