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Machinery and equipment needed to meet the modern scientific and technological progress to improve the friction and wear properties and lubricating properties, not only to the development of high-speed, heavy-duty and high-precision direction, and can extend the life of machinery and equipment, resource conservation and environmental protection significance significant. With good environmental stability of solid lubricant MoS 2 synthesis methods, characterization and performance study. Prepared by the two methods of different nature MoS 2 , to meet its application under different conditions. Dispersant is added to polyethylene glycol, the first with a simple chemical precipitation method the precursor MOS 3 and the precursor at a certain temperature under nitrogen protection, hydrogen desulfurization and incubated for a period of time, prepared MoS 2 particles. Using X-ray diffraction (XRD), scanning electron microscopy (SEM) of the microscopic structure and morphology of the particles were observed characterization, effects of dispersants, desulfurization temperature and holding time on MoS 2 particle size and morphology. Using single factor in the preparation of MoS 3 reaction conditions experiments and orthogonal experiments to study the various factors of MoS 3 yield and to optimize the synthesis conditions. By adding a dispersant to prevent agglomeration of the precursor at high temperature desulfurization stage, get MoS 2 particle size decreases with increasing dispersion dose; desulphurization, with the holding time. MoS 2 crystallinity of the particles increased gradually, gradually transformed into spherical particles by the flower-shaped sheet. The obtained MoS 2 particles have good structural stability and physical and chemical properties, 600 ℃ for desulfurization and holding 8h, the MoS obtained 2 average particle size of 150nm around a spherical structure, free rolling or sliding, with excellent friction properties in aerospace technology has broad application prospects. Surface modification method, oleic acid as a modifier, CTAB supplemented by additives, hydrazine hydrate as the reducing agent, sodium molybdate, sodium sulphide, hydrochloric acid is synthesized from oleic acid modification of MoS 2 nano particles, using orthogonal experimental study of various factors on the MoS 2 yield and optimize the synthesis conditions. By infrared spectroscopy (IR), and thermogravimetric differential thermal analysis (TG-DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and other analytical methods, this surface modifier modified nanoparticles were characterized, and its average particle diameter of 70-100nm, confirmed the carboxyl group of oleic acid MOS 2 the surface of the particles of chemical adsorption, organically modified layer is formed in the surface of the nanoparticles, it is a surface-modifying layer of the hydrophobic oleophilic makes MoS 2 nano-particles with a variety of organic solvents pro reinforcing, which can be stably dispersed in a variety of organic solvents, and its laid the foundation as a lubricant additive. The effects of the calcination temperature of MoS 2 nanocrystals size and morphology, the results show that the calcination temperature reaches 700 ° C insulation 2h MoS 2 crystallite size remained nanoscale, crystalline more complete remains spherical morphology. Oleic acid-modified MoS 2 with good thermal stability, the reasons were explained. And surface modification of MoS 2 particle formation mechanism of assumptions.
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