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A Ni–Cr–MoS 2 coating with trivalent Cr was prepared on the surface of the cylinder liner by the composite co-deposition method to modify its tribology performance. The effects of MoS 2 concentration on the properties of the coatings and tribological properties of cylinder liners were studied by surface detection methods and reciprocating wear tests. The results show that Ni–Cr–MoS 2 coating has a smaller grain size, higher micro-hardness, and greater coating thickness, compared with Ni–Cr coating. Doping by MoS 2 effectively reduces the friction coefficient of Ni–Cr coating from 0.142 to 0.107, the wear amount of coating decreases from 7.9 mg to 7.1 mg, and the scuffing time increases from 19 min to 56 min. It is found that the doping of MoS 2 provided more nucleation sites and promoted the deposition of ions, which resulted in the refined grain and thicker coating. The formation of solid lubrication film by MoS 2 during the wear process and more coating thickness are mainly responsible for the modification of the tribology performance of cylinder liners. This research provides a practical approach to prolong the service life of friction pairs. • The inclusion of MoS 2 significantly increased the Ni–Cr coating thickness. • The doping of MoS 2 increased nucleation sites and changed the coating structure. • The friction and scuffing properties of cylinder liner were significantly improved. • A solid lubrication film produced on the surface of composite coating by MoS 2. [ABSTRACT FROM AUTHOR]

Cashew Nut Shell Liquid (CNSL) has been explored in several applications within the sustainability principles and circular economy of agro-industrial product waste. To understand the anticorrosive and lubricant properties of CNSL solutions, a multi-faceted approach, incorporating electrochemical analyses, immersion test, tribological measurements, and tribochemical characterization was carried out for mild steel AISI 1012, stainless steel AISI 420 and Aluminium Alloy 6061. Electrochemical analyses reveal a positive impact of CNSL, inducing a shift in corrosion potential to more positive values and a decrease in corrosion current, indicating effective corrosion inhibition for stainless steel and aluminium alloy. In mild steel, CNSL exhibits a mixed-type inhibition with efficiency increasing in correlation with oil concentration. The lubricating properties of CNSL are evident according to the coefficients of friction (COF) obtained and the elastohydrodynamic lubrication regime observed during tribological tests. Tribochemical tests demonstrate a reduction in wear and an improvement in tribocorrosion behavior under sliding conditions. CNSL emerges as a promising tribocorrosion mitigator, demonstrating multifaceted benefits. The concentration-dependent effects highlight the need for optimization in specific applications, particularly for passive materials. CNSL not only inhibits corrosion through film formation but also provides effective lubrication, reducing friction, wear, and chemical-mechanical degradation. This research contributes valuable insights to corrosion science. It proposes practical applications for CNSL in diverse industrial contexts, showcasing its potential as an environmentally friendly and sustainable solution for tribocorrosion challenges. • The influence of Cashew Nut Shell Liquid (CNSL) on the tribocorrosion behavior across three metallic alloys (mild steel, stainless steel, and aluminium) is explored. • Electrochemical analyses, immersion test, tribological measurements, and tribochemical characterization was carried out for AISI 1012, AISI 420 and AA6061. • CNSL exhibited a positive impact on corrosion inhibition for stainless steel and aluminium alloy, inducing a shift in corrosion potential to more positive values and a decrease in corrosion current. • CNSL demonstrated lubricating properties according to the coefficients of friction (COF) obtained and the elastohydrodynamic lubrication regime observed during tribological tests. • CNSL emerges as a promising tribocorrosion mitigator, demonstrating multifaceted benefits. [ABSTRACT FROM AUTHOR]

The effect of surface roughness, contact pressure and lubrication on the onset of galling of aluminum 6082-T6 is studied with a pin-on-plate tribometer. The design of experiments involves pins with mean arithmetic roughness Ra equaled to 0.2, 0.35 and 0.6 μm, normal loads ranging from 5 to 600 N, and 4 different lubrications: without lubricant, with MoS2 dry lubricant, with pure mineral oil and with a highly chlorinated paraffin oil. Tests are performed at room temperature and are repeated three times. Experimental results show the great sensitivity of the onset of galling to the roughness and the beneficial effect of dry and liquid lubricants. The occurrence of galling is study by optical micrographs, by the analyses of the coefficient of friction, and by the use of finite element simulations. It comes that the variation of the coefficient of friction is not self-sufficient to detect the onset of galling. The finite element computations involves Wilson's lubrication model and Xue's damage model. Galling is assumed when finite elements near the contact area reach the critical damage Dc. This numerical approach leads to a good prediction of the onset of galling for the tests performed under constant normal load. For tests performed with increasing normal loads and various lubricants, the numerical prediction overestimate the sliding length before galling occurs. • Galling of the aluminium alloy 6082 is predicted by means of finite element computations. • Pin-on-plate tests are performed to study the effect of roughness, contact pressure and lubricant on galling. • Wilson's lubrication model is used to compute the friction stresses, and a damage criteria to detect the onset of galling. • Good agreements are obtained between the numerical predictions of galling and experiments. [ABSTRACT FROM AUTHOR]