Tribological properties of 3 types of MoS₂ additives in different base greases

Abstract

A tribological comparison was conducted among micro‐MoS2 (m‐MoS2), platelet‐like nano‐MoS2, and spherical nano‐MoS2 in lithium grease, lithium‐calcium grease, and polyurea grease, respectively. Micro‐MoS2 slightly improved the lubrication of the 3 greases. The 2 nano‐MoS2 samples had obvious superiority over m‐MoS2. The tribofilms produced by nano‐MoS2 contained MoS2 and MoO3. However, the tribofilms with m‐MoS2 did not contain Mo, or Mo only existed in the form of MoO3. The absence of MoS2 in tribofilms was the main reason for the poor lubrication of m‐MoS2 greases. Moreover, the improved lubrication of the spherical nano‐MoS2 greases than the platelet‐like nano‐MoS2 ones was ascribed to the lubricating superiority of the spherical structure to the platelet‐like one.

Experimental comparison between ZnO and MoS2 nanoparticles as additives on performance of diesel oil-based nano lubricant

“…Its intrinsic lubricity properties relate to the vast space and weak Van der Waals forces between the S-Mo-S sandwich layers and the pure positive charge on the surface, which results in the spread of electrostatic repulsion. Layers are located with the weak molecular forces and can easily slip on each other [11][12][13][14][15] . ZnO nanoparticles are highly regarded for its high surface energy, good dispersion properties, and unique electrical and thermal conductivity.…”

“…Numerous studies have been conducted to investigate the tribological features and thermophysical behaviors of MoS 2 nano-additive oil-based lubricants. The results proved that the lubricity characteristics of the prepared nanofluids is strikingly improved with the corporation of MoS 2 nanoparticles 10,[23][24][25][26][27][28][29][30][31][32][33][34][35] . Cabaleiro et al 36 studied the thermophysical and rheological characteristics of the ZnO nanofluids.…”

Tribological Properties of ZnS(NH2CH2CH2NH2)0.5 and ZnS as Additives in Lithium Grease

“…The use of solid materials as lubricant additives is very important to reduce friction and wear between the sliding surfaces. To reduce wear, several metal sulfides have been experimentally evaluated through comparative analysis of their tribological behaviors, such as MoS 2 [2][3][4], WS 2 [5,6], FeS [7], CuS [8], and ZnS [9][10][11][12][13][14][15][16][17][18]. Among these metal sulfides, ZnS has been investigated under a wide range of operating conditions in the field of tribology.…”

Tribological behavior of zirconium phosphate‐1,4‐dimethylpiperazine compound as lubricant additives

“…As an oil‐based additive, ZrPO 4 ‐DES8 exhibited good tribological behavior with higher load‐carrying and antiwear properties in comparison to typical lubricant additives MoS 2 and graphite under the same test conditions by using a four‐ball tester. The effectiveness of additives depends on various factors, including their compatibility with base oil / lubricant, their crystal structure, sizes, morphologies, concentrations, types of wear‐testing apparatus, and as well as relative motion mode . Thus, it is of great interest to further explore the potential for use ZrPO 4 ‐DES8 as a lubricant additive.…”

“…The effectiveness of additives depends on various factors, including their compatibility with base oil/lubricant, their crystal structure, sizes, morphologies, concentrations, types of wear-testing apparatus, and as well as relative motion mode. 2,[19][20][21] Thus, it is of great interest to further explore the potential for use ZrPO 4 -DES8 as a lubricant additive. ZrPO 4 -DES8 was first synthesised by ionothermal synthetic method; however, this method exhibits some disadvantages of higher costs, low yield, and difficulty for size control, which is a limit for its applications for lubricant additives.…”