Tribological Behaviour of Additive Free Calcium Stearate Greases

Abstract

Two additive free calcium stearate greases have been developed for the requirements of lubrication in automotive components. Two compositions of calcium stearate greases have been prepared by adding 12% and 15% by weight calcium stearate soap in the 450-neutral base oil. Greases have been prepared using the dry technology. The effects of the compositions of calcium stearate soap on the tribological properties of greases have been investigated with the aid of four-ball tester, SRV-Optimol tester, scanning electron microscope (SEM), and transmission electron microscope (TEM). The tribological properties of the additive free greases have been compared with similar application intended commercially available greases containing additives. The structure examinations (before and after weld tests on four ball tester) of the additive free calcium stearate greases have been done using TEM. The FTIR analyses of both synthesized additive free greases have been carried out to study the degradation in greases after weld tests on four-ball tester. It has been observed based on the present investigations that the additive free calcium stearate greases show comparable tribological behavior with commercial greases containing additives.

Keywords

• calcium stearate grease
• dry technology
• additive free
• microstructure
• wear
• sem
• tem
• ftir