The aim to reduce the costs and the mass of hydraulic systems, for the example of an axial piston pump, is getting even more important. To reach this target, it is necessary to optimize the actual hydraulic systems by integrating lightweight designs. An often used design strategy is the so called "material substitution". Typical material substitutions are re-placements of steel-components with polymeric material or hybrid design components. If the substitution is affecting parts of a tribological system, the substitution changes the behaviour of the tribological system in a unknown way. Be-cause of that, parts in a tribological system are mostly excluded from a lightweight design.To use the potential of the lightweight design also in parts of tribological systems, the IPEK developed a test bench, which makes it possible to investigate and characterize different materials for a substitution in the tribological contact between the pistons and the cylinder of an axial piston pump. The descriptions of the contact-modeling as well as first measurement results of the test bench are presented in this paper.