Effect of load/unload process on friction/stiction and durability of head-disk interface

Effect of various operating parameters viz. load/unload speed, disk speed, ramp height, and disk dynamics on load/unload performance, friction/stiction and durability of a head-disk interface (HDI) were studied. Load/unload performance was evaluated using acoustic emission signals and friction force measurements. The load/ unload performance was found to be better for higher load/unload durations, lower disk speeds and higher ramp heights. The effect of ramp height was studied for two different slider suspension designs. A slider suspension with 'A' type suspension design performed well for higher ramp heights. The slider with 'B' suspension design was not affected by a change in ramp height. Disk dynamics studies indicated how strongly HDI can be affected by disk vibrations and supported the effect seen by varying ramp heights. Durability tests revealed that the HDI deteriorated faster for lower ramp heights for a slider with 'A' type suspension design than for the slider with 'B' type suspension design.