The thesis deals with the substitution of conventional materials, particularly with the replacement of metals by polymers. A unified and comprehensive approach for the assessment of substitution potentials was developed. Using a procedural method, data evaluation has been made in order to verify the technical applicability of an alternative component material. Using the example of a hand-held power tools producers product portfolio, this approach was used for identification of all the components with substitution potential. Not only the proof of the fundamental suitability has been delivered, but also the economic aspects, such as competitive advantage through better power to weight ratio or lower manufacturing costs, were taken into account. Additionally to the whole device substitution study, a precise component was selected. For this component, a replacements evaluation, including a material substitution survey, necessary construction adjustments, simulations and tests, have been carried out. As a result, the function of a metallic piston pin was integrated in the piston and connecting rod, which are made of a thermoplastic material. The technical suitability, the cost and the weight advantages were demonstrated. The work bears the characteristics and differences between polymeric materials and metals into account. The combination of a rough and a detailed approach provides an integral examination of the substitution of metals.