Self-lubricating and high wear resistance mechanism of silver matrix self-lubricating nanocomposite in high vacuum

Abstract

The silver matrix self-lubricating nanocomposite with low friction and high wear resistant was fabricated by nanoscale silver powder, nanoscale tungsten disulfide powder and microscale molybdenum disulfide powder. The friction and wear behaviors were investigated, and the worn surfaces were observed and analyzed by SEM and XPSXPS. The investigations on transfer layer and lubricating film were used to analyze the friction and wear properties of the materials, and self-lubricating and high wear resistance mechanism of the nanocomposite was discussed. Decreasing the velocity could increase the thickness of lubricating film, and the thickest lubricating film (about 117 nm) was achieved at a velocity of 0.1 m/s. It is confirmed that the nanocomposite had a significant improvement in friction and wear properties, the low friction coefficient and high wear resistance in high vacuum were 0.125 and 2.53 × 10−6 mm3/N·m, respectively. The transfer layers and lubricating films containing tungsten disulfide and molybdenum disulfide has better self-lubricating property than the transfer layer containing the single solid lubricant. The synergistic effect of binary solid lubricants was confirmed in Nanocomposite.