Tribological analyses of a new optimized gearbox biodegradable lubricant blended with reduced graphene oxide nanoparticles

Abstract

The current work aims to develop a biodegradable lubricant by adding different volume percentages of cashew nut shell liquid (CNSL) in neat castor oil (NCO) and investigating its possibility as replacement to non-biodegradable mineral oil (commercial mineral oil) in industrial applications. The blend exhibiting better tribological properties was additived with different weight percentages of reduced graphene oxide (r-GO) nano-platelets and further tribological tests were performed. The performance of 40%CNSL+NCO was 45.8% better than commercial mineral oil, and with the addition of the 0.5% r-GO in the blend, the performance was improved by 61.7% than the commercial mineral oil. Finally, the novel biodegradable mixture blended with nanoparticles was employed as a lubricant in a gearbox, proving the superiority of the biodegradable lubricant over the commercial mineral oil.

Tribological Behavior and Microstructural Analysis of Atmospheric Plasma Spray Deposited Thin Coatings on Cardan Cross Spindles

“…where h min is the minimum lubricant film thickness, in µm, computed according to the Hamrock and Dowson formula, presented in [43], and R a_lower and R a_upper are the measured arithmetic mean roughness values of the lower and upper discs, respectively. Neglecting the influence of the coating micrometric layer on the overall Young modulus of the coated discs, the corresponding mean values for the λ lubrication parameter in grease lubrication conditions are indicated in Table 5, taking into account the real roughness values of the tested specimens.…”

“…It seems that during rapid tests the lubricant (Mobilux EP2 grease) successfully separated most of the mating surfaces asperity contacts between the lower AISI52100 steel roller and the upper discs testing specimens. The better surface finishing of the uncoated specimens, Test 1 and Test 2, assured lower friction coefficients, as the lubrication regime is dictated by the λ lubrication parameter, given by Equation (1), [ 42 ]: where is the minimum lubricant film thickness, in μm, computed according to the Hamrock and Dowson formula, presented in [ 43 ], and and are the measured arithmetic mean roughness values of the lower and upper discs, respectively. Neglecting the influence of the coating micrometric layer on the overall Young modulus of the coated discs, the corresponding mean values for the λ lubrication parameter in grease lubrication conditions are indicated in Table 5 , taking into account the real roughness values of the tested specimens.…”

Effects of Laser Surface Texturing and Lubrication on the Vibrational and Tribological Performance of Sliding Contact

“…Moreover, Figure 3c shows that the COFs of both the textured and smooth surfaces are reduced by adding graphene to the lubrication oil. This is due to the fact that graphene has an ultra-thin layered structure, which is easy to adhere to the frictional contact surfaces and reduce the direct contact between the friction counterparts [35][36][37].…”

Wear and Rolling Contact Fatigue Analysis of AISI 52100 Bearing Steel in Presence of Additivated Lubricants

“…The anti-wear properties of the lubricant samples were investigated using a four-ball tribometer following the ASTM 4172 standards [18]. The four-ball machine is from TR30 series (Model number: TR 301; Software: WINDUCOM; Make: DUCOM, Bengaluru, India).…”