Layered Double Hydroxide Nanoplatelets with Excellent Tribological Properties under High Contact Pressure as Water-Based Lubricant Additives

Abstract

High efficient and sustainable utilization of water-based lubricant is essential for saving energy. In this paper, a kind of layered double hydroxide (LDH) nanoplatelets is synthesized and well dispersed in water due to the surface modification with oleylamine. The excellent tribological properties of the oleylamine-modified Ni-Al LDH (NiAl-LDH/OAm) nanoplatelets as water-based lubricant additives are evaluated by the tribological tests in an aqueous environment. The modified LDH nanoplatelets are found to not only reduce the friction but also enhance the wear resistance, compared with the water-based cutting fluid and lubricants containing other particle additives. By adding 0.5 wt% LDH nanoplatelets, under 1.5 GPa initial contact pressure, the friction coefficient, scar diameter, depth and width of the wear track dramatically decrease by 83.1%, 43.2%, 88.5% and 59.5%, respectively. It is considered that the sufficiently small size and the excellent dispersion of NiAl-LDH/OAm nanoplatelets in water are the key factors, so as to make them enter the contact area, form a lubricating film and prevent direct collision of asperity peaks. Our investigations demonstrate that the LDH nanoplatelet as a water-based lubricant additive has a great potential value in industrial application.

PEG‐assisted solvothermal synthesis of MoS2 nanosheets with enhanced tribological property

“…1,2 For the past decades, nanoparticles have attracted considerable attention as potential oil additives due to their excellent physical and chemical properties. 3 In respect of this, the layered nanoparticles based on strong intraplanar and weak interplanar bonds, such as graphite and its derivatives, 4 hexagonal boron nitride, 5 zirconium phosphates, 6 layered double hydroxides, 7 and transition metal dichalcogenides 8,9 have been recognised as promising alternatives for traditional oil additives. Molybdenum disulfide (MoS 2 ) nanoparticles, as a typical member of transition metal dichalcogenides, are known to enhance the tribological properties of oils in virtue of their excellent frictionreducing and antiwear properties.…”

Entwicklung von galvanisch gekoppelten Gleitlagern zur Reduzierung von Reibung und Verschleiß

“…Bei For-K schungsarbeiten, die sich mit der Untersuchung der makroskopischen Reibung beschäftigen, stehen Additive zur Optimierung von Wasser als Schmierstoff im Fokus. Dazu werden in wissenschaftlichen Arbeiten MoS2 Nanopartikel [22], CuO-beschichtete Nanopartikel [23], geschichtete Doppelhydroxid-Nanoplättchen [24], fluoriertes Graphen [25], Lithiumsalz und nichtionische Tenside [26], oxidierte aus Holz stammende Nanokohlenstoffe [27], Pflanzenextrakte [3] und ILCs [28] diskutiert. Es wurde herausgefunden, dass das Einlaufverhalten zum Erreichen extrem niedriger Reibung einen entscheidenden Einfluss bei der Verwendung einer wässrigen Mischung mit Schwefelsäure und Glycerin hat [29].…”

Macroscale Superlubricity Achieved With Various Liquid Molecules: A Review

“…The superlubricity mechanism for BN-containing PAO at Si 3 N 4 /DLC interface is the contact area reduction because of BN as nanoscale ball bearings lead to the point-like contact, and the weak van der Waals interaction force between BN molecules . The superlubricity mechanism for LDH is regarded as its small size and good dispersion in water make LDH enter the contact area and form an effective lubricating layer, and therefore protect the asperity peaks from direct collision (Wang et al, 2016). Additionally, nanodiamonds glycerol colloidal solution was found to achieve superlubricity and low wear, which are due to the hydrodynamic effect, hydrogen bond layer, and rolling effect of nanodiamonds (Chen et al, 2016).…”