Tribological investigations of metallic layers of flexible substrates

The tribological behavior of unprotected thin metallic layers on flexible substrates was studied in sliding contact with magnetic heads. Microscopic investigations of the wear mechanism give evidence that microploughing of the metallic layer with plastic deformation of the substrate takes place during the first passes of the magnetic head. Subsequent surface fatigue of the layer system initiates debris, which causes a drastic increase of the coefficient of friction and a sudden decrease of the readout signal. Key parameters for improving the lifetime are the reduction of defects and the evolution of reliable lubricating top coatings