Newly developed friction tester for in situ soft X-ray absorption measurements of frictional engine-oil/metals interfaces

Abstract

A novel friction tester has been developed to clarify the friction mechanism between engine oil and metals by in situ/operando measurements of the X-ray absorption near edge structure (XANES) using the total electron yield (TEY) method. The tester can perform frictional motion with engine oil and metals in a vacuum chamber under a vacuum of 10-7 Torr during TEY-XANES measurements in BL-6.3.2 at the Advanced Light Source (ALS). From in situ XANES measurements in the C K and Fe L regions, the organic molecule layers at the oil/metals interfaces have been successfully observed.