Highly loaded machine elements are a cornerstone of many technical systems, such as combustion engines, transmissions or electrical drives. Due to challenging legislative requirements regarding fuel consumption and emissions for the automotive industry and the advent of electric cars, the development of new simulation and test methods for the evaluation of alternative tribosystems is inevitable. As a part of this thesis a new simulation framework, which is equally applicable for lubricated and dry contacts and can consider coatings and surface microstructures, was developed. Due to the direct integration of the surface roughness into the simulation the prediction of the coefficient of friction (COF) can be improved by up to 75% compared to state of the art methods. The validation of the simulation framework was carried out by a two-disc machine, which was developed further as a part of this thesis too. The test-rig was extended significantly by means of a mechanical redesign and by introducing completely new electrical, control and sensor systems. The results obtained by the developed simulation and experimental methods show an excellent agreement to findings made in other publications. Further work was carried out in order to apply the developed methods for the analysis of alternative materials in highly loaded machine elements. Diamond-like-carbon (DLC) coatings in combination with a steel counterpart were investigated under conditions relevant for modern combustion engines. Results revealed that the COF under boundary lubrication is increasing by up to 20%, depending on the oil-temperature, due to the formation of tribofilms on the steel surface. Also, high performance polymers, as for example PA46 or PPA, were tested under dry conditions against steel regarding their applicability in tribo-systems with high sliding speed. Results indicated, that a nickel coating of the steel specimens greatly enhances the overall tribological behaviour. The created methods present a valuable tool in order to meet future requirements in the field of friction optimisation. Additionally, the applied investigations of alternative materials will serve as a foundation for future research projects in order reduce the energy consumption of highly loaded machine elements during manufacturing and usage period.