Ruscher Céline, Rottler Jörg
Institut Charles Sadron, 23 rue du Loess, F-67034 Strasbourg, France.
Department of Physics and Astronomy and Quantum Matter Institute, University of British Columbia, Vancouver, BC V6T 1Z1, Canada.
Soft Matter. 2020 Oct 7;16(38):8940-8949. doi: 10.1039/d0sm01155j.
The distribution of local residual stresses (threshold to instability) that controls the statistical properties of plastic flow in athermal amorphous solids is examined with an atomistic simulation technique. For quiescent configurations, the distribution has a pseudogap (power-law) form with an exponent that agrees well with global yielding statistics. As soon as deformation sets in, the pseudogap region gives way to a system size dependent plateau at small residual stresses that can be understood from the statistics of local residual stress differences between plastic events. Results further suggest that the local yield stress in amorphous solids changes even if the given region does not participate in plastic activity.
采用原子模拟技术研究了控制无热非晶态固体中塑性流动统计特性的局部残余应力(失稳阈值)分布。对于静态构型,该分布具有伪能隙(幂律)形式,其指数与整体屈服统计结果吻合良好。一旦开始变形,伪能隙区域就会在小残余应力下让位于与系统尺寸相关的平台,这可以从塑性事件之间局部残余应力差的统计中得到理解。结果还表明,即使给定区域不参与塑性活动,非晶态固体中的局部屈服应力也会发生变化。