Mechanical properties and wear characteristics of various thin films for rigid magnetic disks

The relationships between mechanical properties and wear characteristics are described for carbon, SiO/sub 2/ and CoNi-on-Cr thin films. The films are prepared on various rigid substrates in the submicron thickness range by RF magnetron sputtering. Mechanical properties examined include microhardness, Young's modulus and internal stress. Wear resistances are evaluated for thin films sliding against a thin film head Al/sub 2/O/sub 3/-TiC slider. There is no correlation between the microhardness and the wear resistance. However, the load-indentation depth curves provide useful information, since the curve profile varies reflecting the presence of microdefects closely related to wear characteristics. A clear and common relationship holds between Young's modulus and wear resistance which is a maximum at 0.8-0.9 times the modulus. The wear resistance of CoNi films decreases as the tensile stress increases in the Cr substrates. The properties of carbon films depend on their own internal stress; an increase in compression stress leads to deterioration in their wear resistance.<
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