Influence of surfactants on tribological behaviors of MWCNTs (multi-walled carbon nano-tubes)

Abstract

Multi-Walled Carbon Nano-Tubes (MWCNTs) are employed as anti-wear and anti-friction additives in mineral oil. The MWCNTs are known for their superior thermal conductivity, mechanical and optical properties. It is expected that hollow-core carbon nano-tubes provide easy sliding as well as rotating action with respect to one another; therefore, there is a need to explore the use of MWCNT as lubricant additive. In the present research work, experimental investigations have been conducted to explore the importance of the MWCNTs as additives in the lubricating oils. Tests were performed on three oil samples: Sample 1 (Base oil), Sample 2 (MWCNT with base oil) and Sample 3 (MWCNT and surfactant with base oil), by employing block on disc set-up. To understand the role of surfactant on MWCNT towards reducing the friction and wear, sensitivity analysis performed using fractional factorial table has been detailed. The results of cumulative wear and friction have been reported in this study.

Inorganic nanomaterial lubricant additives for base fluids, to improve tribological performance: Recent developments

“…The analysis results show that adding MWCNT nanoparticles to the base oil reduces wear and produces a smoother surface with fewer scars, further confirming that the addition of MWCNTs can effectively reduce direct metal-to-metal contacts. The MWCNT nanoparticles deposited on the worn surface reduce the shearing stress, thereby enhancing the tribological performance [58]. Gong et al [59] found that when added as an additive to polyalkylene glycol-based oil, the CNTs could significantly improve the oil's friction-reduction and anti-wear capabilities, by forming boundary lubrication films.…”

Taguchi optimization of various parameters for tribological performance of polyalphaolefins based nanolubricants

“…3,[8][9][10][11][12][13][14][15] It is reported that MWCNTs are effective in many tribological applications by their distinctive structure, high flexural and tensile strengths and high elastic modulus. [16][17][18][19][20] The hollow core carbon nanotubes are slippery and facilitate for rotating action relative to each other because of such action, MWCNTs forms close to optimal nano bearing. 20 It was also reported that modification of MWCNTs with functional groups (organic compounds) resulted in advancement in the dispersion stability of MWCNTs as well as in the tribological properties of lubricants.…”

“…[16][17][18][19][20] The hollow core carbon nanotubes are slippery and facilitate for rotating action relative to each other because of such action, MWCNTs forms close to optimal nano bearing. 20 It was also reported that modification of MWCNTs with functional groups (organic compounds) resulted in advancement in the dispersion stability of MWCNTs as well as in the tribological properties of lubricants. 16,17,19,21 From the above discussion, it is clear that limited research work is reported on the tribological properties of MWCNTs in PAO oils.…”

Lubricated tribology of hybrid AMMC–steel sliding contact: A comparative investigation between fully formulated commercial engine oils and surfactant functionalized MWCNT–base oil formulation

“…27 Hence, nonfunctionalized MWCNT with suitable surfactants can be a useful approach in preparing homogenous and stable suspensions. 28 It has already been found that surfactant can be used to enhance the stability of nanomaterials in lubricants. 21…”