Investigation of tribological and read-write performance of textured sliders
Slider surface texturing is a promising new way to improve the tribological performance of future hard disk drives with very low flying heights. In this study, proximity recording sliders with a design flying height of 6 nm at 20 m/s were textured using oxygenated plasma etching. In order to protect the read-write element, texturing of sliders was performed after positioning a mica mask over the read-write element. The tribological and read-write performance of the slider before texturing was compared with the tribological and magnetic performance of the same slider after texturing. It was found that no degradation of the read-write performance occurred and that the tribological performance of the slider was improved after texturing.
Tribology of textured sliders in near contact situations
Island-type texture was fabricated on two types of picosliders using plasma sputtering and ion beam etching. Laser-Doppler interferometry was used to investigate the vibrations of the textured and untextured sliders in near contact situations. Lubricant redistribution on the disk surface caused by slider/disk interactions was investigated using scanning ellipsometry [surface reflectance analyzer (SRA)]. The results show that texture on the slider surfaces reduces in-plane and out-of-plane slider vibrations. Textured sliders were found to cause less lubricant depletion on the disk surface than untextured sliders.
EFFECT OF SAMPLE PREPARATION ON WATER TREE RESISTANCE OF XLPE/SEBS BLENDS
The effects of an aromatic polymer, such as poly[styrene-b-(ethylene-co-butylene)b-styrene] (SEBS), and its preparation processes on water tree resistance, morphology, crystallinity, dielectric constant and dielectric loss tangent of crosslinked polyethylene (XLPE)/SEBS and XLPE/SEBS/ethylene vinyl acetate (EVA) blends were investigated. The XLPE/SEBS samples were characterized by means of differential scanning calorimetry, scanning electron microscopy, dielectric spectral analysis and the accelerated water treeing experiment. The results clearly showed that although SEBS was partially compatible with LDPE and it was dispersed evenly in XLPE matrix, the blends demonstrated excellent dielectric performances, such as dielectric constant and dissipation factor. The crystallinity of XLPE/SEBS blends was decreased with increase in SEBS content and it was further decreased with the addition of EVA. SEBS could effectively improve the water-tree resistance of XLPE and both SEBS and EVA were found to improve the water tree resistance of XLPE synergistically as expected. The differences in sample preparation processes could change the phase morphology and dielectric performance of the blends, and could also influence the dispersion of SEBS in XLPE matrix as well as the crystallinity of the blends. Different preparation processes led to different water tree resistance behaviours of the samples. The improvement of SEBS dispersion in XLPE matrix helped to improve the water tree resistance of XLPE.