Enrique RA, Bellon P
Department of Materials Science and Engineering and Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Phys Rev Lett. 2000 Mar 27;84(13):2885-8. doi: 10.1103/PhysRevLett.84.2885.
We study an alloy system where short-ranged, thermally driven diffusion competes with externally imposed, finite-ranged, athermal atomic exchanges, as is the case in alloys under irradiation. Using a Cahn-Hilliard-type approach, we show that when the range of these exchanges exceeds a critical value labyrinthine concentration patterns at a mesoscopic scale can be stabilized. Furthermore, these steady-state patterns appear only for a window of the frequency of forced exchanges. Our results suggest that ion beams may provide a novel route to stabilize and tune the size of nanoscale structural features in materials.
我们研究了一种合金体系，其中短程热驱动扩散与外部施加的有限程无热原子交换相互竞争，这在受辐照合金中就是这种情况。使用一种相场Cahn-Hilliard型方法，我们表明，当这些交换的范围超过临界值时，介观尺度上的迷宫状浓度模式可以得到稳定。此外，这些稳态模式仅在强制交换频率的一个窗口内出现。我们的结果表明，离子束可能为稳定和调节材料中纳米级结构特征的尺寸提供一条新途径。
