A dispersion of stiff and thin (‘rigid line’) inclusions (RLIs) in a matrix material may result beneficial for stiffening in the elastic range, but might be detrimental to strength, as material instabilities may be triggered by inclusions when the matrix is brought to a viscoplastic-damaging state. This dual role of RLIs is investigated by means of the embedded reinforcement model. Validated against available analytical predictions, this numerical model is employed to assess the roles of RLIs’ orientation, interaction, volume fraction, and distribution, considering up to 1500 inclusions. When the matrix material deforms inelastically, RLIs produce stress concentrations that promote the nucleation of shear bands. These are characterized at collapse for many distributions of RLIs, showing that their effects range from almost negligible to a disrupting alteration of the dominant failure mechanism. In the latter case, it is shown that the dominant shear bands can be fragmented by RLIs into a mosaic of tiny localization bands. These results offer new insights into energy dissipation mechanisms of reinforced materials, as they are promoted or inhibited by the interactions of rigid line inclusions.

刚性和稀薄（“刚性线”）夹杂物（RLI）在基体材料中的分散可能有益于弹性范围内的硬化，但可能不利于强度，因为当带入基体时，夹杂物可能触发材料的不稳定性变成粘塑性破坏状态。RLI的这种双重作用通过嵌入式增强模型进行了研究。根据可用的分析预测进行了验证，该数值模型用于评估RLI的方向，相互作用，体积分数和分布的作用，最多考虑1500个夹杂物。当基体材料发生非弹性变形时，RLI会产生应力集中，从而促进剪切带成核。这些特征是许多RLI的分布都崩溃了，表明它们的影响范围从几乎可以忽略不计到破坏性主要失效机制的改变。在后一种情况下，显示出主要的剪切带可以被RLI分割成微小的定位带的镶嵌。这些结果为增强材料的能量耗散机理提供了新的见识，因为它们受刚性线夹杂物的相互作用促进或抑制。