Experimental and numerical investigations of the magnetic head/tape interface

In high density magnetic tape recording systems, the magnetic head is in contact with the magnetic tape causing reliability problems of the tape drive. Premature failure and data reliability can be improved by the fundamental understanding of tribology and mechanics of the magnetic head/tape interface.; Three-wavelength interferometry was used to measure the contact spacing of the head/tape interface. Glass replica heads with different geometry parameters were used to investigate the effect of head contour on the head/tape spacing. Different metal particle tapes were used to study the effect of tape compliance, tape speed and tape tension. The compressibility of asperities on the tape surface was investigated by measuring the mean contact spacing as a function of mean contact pressure for a tape sample pressed against a flat glass plate by air pressure. The so-called "asperity compliance" was used to determine mechanical properties of flexible medium surfaces and to analyze the effects of tape structural parameters and manufacturing processes on the contact spacing.; The finite element method with an improved head/tape contact model was used to simulate the head/tape interface. The simulation results agree well with spacing measurements. The effect of design parameters on the head/tape interface was investigated.; The nano- and macro-wear characteristics of tape head materials were investigated using nano-scratch testing and wear bar testing. The micro-indentation method was used to investigate wear of the head/tape interface in a linear tape drive. The results from nano- and macro-wear tests were analyzed and correlated with the microstructure of the materials.; In addition, the correlation between tape surface roughness and medium noise was investigated using both mechanical and magnetic recording measurements.