Observation of Hydrogen Permeation into Fresh Bearing Steel Surface by Thermal Desorption Spectroscopy

Abstract

This paper describes an experimental study on permeation of hydrogen into bearing steel through fresh surface with thermal desorption spectroscopy. Sliding experiments using a lapping machine with and without lubricant were conducted to generate fresh surfaces. Desorption spectra were taken before and after sliding, and the surfaces were analyzed with X-ray photoelectron spectroscopy. It was found that oxide and/or hydroxide film was formed on the surface, whereby hydrogen was generated and diffused into the bulk steel. When heated, some of hydrogen in the steel reacted with the surface film to be desorbed as water, while some other hydrogen was desorbed in the form of hydrogen molecules. Hydrogen desorption spectra in combination with water desorption spectra thus provides information not only on hydrogen permeated but also on surface oxide/hydroxide film.