Study of Rheological Behavior of Olive Oil Used as Biodegradable Lubricant

In this article, based on experimental data, we obtained three dependence relations of dynamic viscosity versus temperature by polynomial and exponential fitting. The correlation coefficients have values close to unity which proves that the obtained relations accurately describe the non-Newtonian behavior of olive oil.

On the Tribological and Oxidation Study of Xanthophylls as Natural Additives in Castor Oil for Green Lubrication

The present study focuses on an introductory analysis of the use of three xanthophylls as additives for green lubricant applications. For this purpose, the additives were characterized by FTIR and 1H-NMR techniques, and the bio-lubricants were described by their physical properties. The effect of the natural compounds on the friction and wear properties of bio-lubricants were evaluated by sliding friction tests under boundary conditions, as confirmed by an analysis of the lubricating film thickness. The antioxidant capacity was analyzed by FTIR spectroscopy. It was observed better wear protection in castor oil with xanthophylls than without these additives. The wear rate was reduced up to 50% compared with neat oil. Lesser beneficial effects were appreciated in friction coefficient since it was increased 25%. The best contribution was observed with astaxanthin as an additive. In addition, a significant improvement in the oxidation of castor oil, complemented with this additive, was exhibited by FTIR analysis. It was found that xanthophylls could be employed as additives for totally biodegradable lubricant applications since they have better tribological and antioxidant behavior than current additives.

Study Rheological Behavior of Rapeseed Oils Compared to Mineral Oil

This article presents the dependence of dynamic temperature viscosity and shear rate for rapeseed oils used as biodegradable lubricant and SAE 10W. The studied rheograms show the dependence of the dynamic shear rate viscosity as well as the dependence of the dynamic temperature viscosity. From the rheograms there is a decrease in the dynamic viscosity with temperature and shear rate for the two oils. The dynamic viscosity of rapeseed oil is most strongly influenced by the shear rate compared to the studied SAE 10W oil. The rheological behavior of rapeseed and mineral oil SAE 10W was studied with the Haake VT 550 viscometer at temperatures between 40 and 1000C.

Rheological Characteristics of Castor oil used as Biodegradable Lubricant

In this article I have presented the rheological characteristics of castor oil used as a biodegradable lubricant. The rheograms of castor oil have quite different slopes. The highest slope is at shear speed 3.3s-1, and the smallest slope is at 120s-1. From the representation of the dependence of the dynamic viscosity on the correlation coefficients at all the temperatures at which the castor oil has been was studied, the correlation coefficients have values close to the one value. The correlation coefficients have values between 0.985-0.990.