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• The highlights of this work can be seen in several focal points. First, the parameters slip amplitude, contact pressure and fatigue loading were investigated independently of each other, for the material groups of cast iron and aluminum on a special test bench. It was thus possible to experimentally determine three-dimensional fretting maps (fretting fatigue strength versus slip amplitude and contact pressure). In this way, a worst-case parameter combination of slip amplitude and contact pressure could be determined, which served as the basis for the development of a calculation concept. • The second highlight is the developed calculation rule itself. This is based on the FKM guideline from Germany and extends it to include the aspect of fretting fatigue. The FKM guideline is a robust guideline for engineers and designers. With the extended method, they now have the possibility to calculate fretting fatigue components in a practical way, which was not possible before. • The third highlight is the validation of the developed method on realistic connecting rod components. With the new calculation method, it was possible to achieve a significant increase in calculation accuracy (in contrast to the classic FKM guideline). The original error of up to 90% in the determination of the degree of utilization was reduced to a maximum error of 18.7%. Many components made of cast iron (e.g., in combustion engines) and aluminium (e.g., in aircraft construction) are subject to fretting fatigue. This results in a need for a method for assessing the strengths of the aforementioned materials that takes into account the reduction in fatigue strength due to fretting as well as the accompanying reduction in service life. In a first paper, the authors already presented a calculation method for the fail-safe design of steel–steel contacts subject to fretting fatigue. This enables the engineer or designer to perform a strength assessment for any component connection made of steel. The calculation method is based on a tribological worst-case assumption and can be integrated into the analytical strength assessment of the internationally known FKM Guideline. The strength reduction is taken into account by use of empirically determined fretting factors. The frequent failures of component connections made of cast iron and aluminium in the field made an extension of the calculation method became necessary. This work therefore includes experimental investigations into the materials EN-GJS-700, EN-GJS-400 and EN-GJL-300 (cast iron), as well as EN AW-7075 T651, EN AW-6082 T651 and EN AW-5083 (aluminium). Since the main parameters determining fretting fatigue strength are slip amplitude and contact pressure, the worst-case combinations of these parameters (resulting in the lowest friction fatigue strength) were first determined for each of the two material groups using a laboratory test setup. These parameters could be found at s a = 10 μ m ; p = 40 M P a for cast iron and s a = 5 μ m ; p = 10 M P a for aluminium. Based on these worst-cases, the fretting fatigue limits of the aforementioned materials were determined, as well as the effect of mean stress. The fretting factors of the materials were derived from the experimental results. Additional experimental investigations using a connecting-rod-like geometry served to validate an application typical of the industry. Using the calculation method, the degree of utilisation of the connecting rods could be determined with good accuracy (maximum error: 18.7 %). [ABSTRACT FROM AUTHOR]