Some differential relations of inert wear- and attrition work mechanisms, derived in a parallel paper, are here applied. The consideration of relevant and suitable boundary conditions is called for. For ductile- and brittle-type target materials, one may often establish a direct- or proportional connection between the relevant sub-process work mechanism – referred to as wear work or attrition work – and corresponding net resulting wear- or attrition rates. Kinetic theory can be supportive in estimating model coefficients. In addition, additional thermodynamic considerations may be necessary, in order to estimate behavior at extremum conditions. The direct connection is demonstrated for the differential process of ductile wear, which encompasses most types of macroscopic-scale ductile erosion and 2-body- and 3-body ductile abrasion situations. The direct connection is also demonstrated for brittle erosion, and for impact wear. It is shown that the size effect on ductile erosion and abrasion – a hitherto not understood phenomenon – can also be explained by this connection.