Magnetic and tribological evaluation of metal particle and metal-evaporated tapes in a linear tape drive

Abstract

Improving the performance of computer tape drives is an ongoing process that has recently involved the utilization of metal-evaporated (ME) tapes. The magnetic and tribological performance of the current metal particle (MP) tape and a new dual-magnetic-layer ME tape were evaluated in a Quantum DLT 4000 linear tape drive. Head output, drop-outs and head-tape interface friction were monitored during high-tension (1.7 N) high-speed (4 m/s) short-pass (10 m) shuttling tests without stepping the head. The severe MP test never showed signs of failure, but wear of the head's outriggers is believed to impact the stability of the head output signal. MP tape significantly outperformed ME tape; ME even performed poorly at nominal tension (0.8 N) and speed (2.5 m/s) conditions. ME tape lubricant was stripped away by corners on the DLT head, resulting in increased friction, wear and exposure of the relatively brittle diamond-like carbon layer. A high-tension high-speed MP test with head stepping was also performed to evaluate the effect of stepping; it failed far sooner than the non-step MP test. The nominal ME test and severe MP head step test are both believed to have failed because of the drive's inability to overcome high (wear-induced) static friction experienced during changes in tape direction. Modifications to the existing head or a new head design could improve the performance of ME tape in the DLT 4000 linear tape drive.