  The wear volume is known to keep increasing during frictional processes, and
Archard notably proposed a model to describe the probability of wear particle
formation upon asperity collision in a two-body contact configuration. While
this model is largely adopted in the investigations of wear, the presence of
wear debris trapped between the surfaces changes the system into a three-body
contact configuration already since the early stages of the process. In such a
configuration, a significant amount of wear is produced at the interface
between the trapped debris and the sliding bodies. Here, relying on analytical
models, we develop a framework that describes crack growth in a three-body
configuration at the particle-surface interface. We then show that crack growth
is favoured within the sliding surfaces, instead of within the debris particle,
and test such result by means of numerical simulations with a phase-field
approach to fracture. This leads to an increase in the wear volume and to
debris particle accretion, rather than its break down. The effects of adhesion,
coefficient of friction, and ratio of the applied global tangential and normal
forces are also investigated.
