but does have an effect on its location. Furthermore, disorder clearly plays an important role also in the experimental systems since QB and D1 responses are typically observed experimentally and we show that these occur only in presence of disorder. Our results confirm that knowing the average value of the bond strengths might not be enough to predict the failure regime, in agreement with recent phenomenological models aiming to capture softening and the Mullins effect in double networks [@Vernerey2018].

\[sec:MicroResponse\] Failure at the microscopic level
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In the previous section, we found that the macroscopic force balance reasonably captures the transition from (quasi)brittle to ductile fracture in the RSN model and that disorder influences this transition. Furthermore, we have seen in Fig. \[fig:StressStrain\](b)-(e) that as long as some disorder is present distinct failure patterns develop in the RSN that suggest a tight link between the macroscopic and microscopic failure process. In this section, we explore several indicators of microscopic failure in disordered RSN systems, with a special focus on stress heterogeneity, and we consider to what extent the force balance influences the microscopic failure processes in double networks.

### The fraction of broken bonds

![Rescaling of the fraction of broken 