Investigation on wear and recession of the GMR head in helical-scan tape systems

Using the shielded spin-valve GMR head and the optimized metal evaporated tape in helical-scan tape system, it is almost feasible to achieve areal density at 11.5 Gb/in/sup 2/. This is because of the signal-to-noise performance of electromagnetic property. In practice, however, it is necessary to eliminate the problem of the head wear of the GMR head more than it is to increase performance of the electromagnetic properties. One approach is to modify the head microstructure, changing it into the flux guide type at the expense of the electromagnetic properties. Another thing is to manage to do so without electromagnetic property deterioration, using the shielded spin-valve GMR head. In this report, we have investigated the latter approach and not only estimated the wear quantity of the GMR head but also measured its recession quantity in accelerated dust environment, taking into consideration the actual operating conditions.