Technical-grade MoS2 powder with an average particle size of 10 micrometers was used in this study. The size ranged from less than 1 micrometer to 75 micrometers; however, the large particles appeared to be conglomerations of small particles. The riders and disks were made of 440C HT stainless steel with a Rockwell hardness of C -58 to C -60. The disks were lapped and polished to a surface finish of 0.09iO. 02 micrometer CLA (centerline average). Some disks were then roughened by sanding them randomly with number-150-grit wet sandpaper to 0.30*0.05 micrometers (CLA) or by sandblasting them to 1.2h0.2 micrometers (CLA). The MoS2 powder was applied to the polished or roughened disk surfaces by mech- manically rubbing it over the surface at constant load (see section PROCEDURE).
The thickness of the films obtained was estimated optically and by surface, profilometry to be about 1 to 2 micrometers above the highest feature on the metallic surface. A pin-on-disk sliding friction apparatus was used in this study. This apparatus is described in reference 14. The friction specimens (fig. 1) were a flat disk (6.3 cm diam) in sliding contact with a stationary hemispherically tipped rider (0.476 cm radius). The rider slid on a 5-centimeter-diameter track on the disk for a linear sliding speed of 2.6 meters per second at a disk rotation of 1000 rpm. The apparatus used to apply the MoS2 powder to the disks is shown in Figure 2. The disk was attached to the vertical shaft of a small electric motor utilizing a cup-shaped holder. Two vertical rods restrained a floating metal plate attached to the MoS2 applicators. In these experiments, the backs of polishing cloths were used as applicators. The rubbing load was applied by placing two l-kilogram weights on the metal plate. If you are looking for high quality, high purity, and cost-effective Molybdenum disulfide or the latest price, please email contact mis-asia.
