HIGH FRICTION COEFFICIENT MATERIALS

Abstract

This paper presents some insights into the materials characterised by the high friction coefficient. Friction coefficient is one of the essential parameters for evaluation of the contact development, but it still needs further investigations, especially from nano and micro aspects. There are several approaches to the determination and quantification of the static and dynamic coefficients, whereas methodology involving energy dissipation has gained attention for the nano and micro contacts. High friction is applied in systems where good adhesion is needed, such as breaks or in the case of dry adhesives – fitting of the elements together. Material combinations are reviewed, that exhibit high friction coefficients during contact. Two types of materials are presented from friction aspects: Ti-based alloys for medical implants where high friction is a negative property and Al-based alloys for which this feature has been used in various friction welding applications. In the case of Ti-based alloys, many approaches have been tried to overcome high friction and associated high detrimental wear, but it is still the evident problem. For aluminium alloys, it is used for joining two parts in different systems, such as car body, ship elements, or various rail wagon related elements.