No abstract

Purpose This study aims to reduce the harm of industrial lubricants to consumers. Composite aluminum-based grease (CAG) was prepared, and medical-grade montmorillonite (M-MMT) was used to improve the antiwear performance of the prepared grease. Design/methodology/approach The influence of the additive (M-MMT) on the tribological performance is mainly investigated using a ball-disc wear tester, and the wear scar surface about the disc was characterized by white light interferometer and electrochemical workstation. Moreover, the cell viability test was used to evaluate the safety of the grease. Findings The results indicated that for the grease containing 1.5% M-MMT, the average coefficient of friction was reduced by about 46% compared with the CAG, the wear volume of the disc reduced by about 74%. Moreover, CAG and 1.5% M-MMT-containing CAG were proved safety by means of the cell viability test. Originality/value The integral properties of CAG can be improved with the medical-grade materials as the additives, while ensuring the safety.

To improve the lubricity of the as‐prepared food‐grade calcium‐based grease, the effects of nano‐additive carbon nano onions (CNOs) on the tribological properties are systematically investigated using a ball‐disc wear tester. The properties of CNOs‐containing food‐grade calcium sulfonate complex greases (CSCG‐FG) were characterised by thermogravimetric analyser, rheometer and electrochemical workstation, Listeria monocytogenes, X‐ray photoelectron spectrometer and Raman spectrometer. The results revealed that pure and CNOs‐containing CSCG‐FG were proved to be safe. The average coefficient of friction (aCoF) and wear volume of the disc at CSCG‐FG of 0.10 wt% CNOs were the minimal values, which were 31.4 and 70.0% less than that of pure CSCG‐FG at 25°C and greatly lower than that of similar commercial food‐grade grease. At high temperature, CNOs‐containing CSCG‐FG had lower aCoFs and torques. CSCG‐FG of 0.10 wt% CNOs would be most possibly used in engineering applications and the results will provide valuable insight into developing food‐grade lubricants.