Slip-free multiplication and complexity of dislocation networks in FCC metals
Slip-free multiplication and complexity of dislocation networks in FCC metals
复制标题
FCC 金属中位错网络的无滑移倍增和复杂性
作者：
S. Akhondzadeh;N. Bertin;R. Sills;W. Cai
在结晶固体的塑性变形过程中，位错线的复杂网络形成并演化。为了捕捉位错密度的演变，晶体塑性的主要理论假设：1）倍增是由活动滑移系统中的滑移驱动的，2）成对滑移系统相互作用主导网络演变。在这项工作中，我们分析了超过100个离散位错动力学模拟（抑制交叉滑移）的庞大数据库，我们的研究结果使这两个假设都受到质疑。我们表明，位错增殖是常见的滑移系统，没有施加应力和塑性应变率，我们称之为无滑移增殖的现象。我们表明，虽然形成的滑动路口提供了一种机制，无滑移乘法，额外的机制，占共面相互作用的影响，需要充分解释的意见。与由一对滑移系统之间的二元反应产生的滑动结形成不同，这些新的倍增机制需要更高阶的反应，从而导致复杂的网络结构。虽然这些复杂的配置以前没有得到太多的关注，但它们占我们数据库中线交叉点的50%左右。
During plastic deformation of crystalline solids, intricate networks of dislocation lines form and evolve. To capture dislocation density evolution, prominent theories of crystal plasticity assume that 1) multiplication is driven by slip in active slip systems and 2) pair-wise slip system interactions dominate network evolution. In this work, we analyze a massive database of over 100 discrete dislocation dynamics simulations (with cross-slip suppressed), and our findings bring both of these assumptions into question. We demonstrate that dislocation multiplication is commonly observed on slip systems with no applied stress and no plastic strain rate, a phenomenon we refer to as slip-free multiplication. We show that while the formation of glissile junctions provides one mechanism for slip-free multiplication, additional mechanisms which account for the influence of coplanar interactions are needed to fully explain the observations. Unlike glissile junction formation which results from a binary reaction between a pair of slip systems, these new multiplication mechanisms require higher order reactions that lead to complex network configurations. While these complex configurations have not been given much attention previously, they account for about 50% of the line intersections in our database.
影响因子：
9.4
作者：
M. Stricker;D. Weygand
通讯作者：
M. Stricker;D. Weygand