Formation of lubricant and other films on clean metal surfaces: a study by electron diffraction

Abstract

In a recently published paper (Courtel 1950), the author has collected the results of researches carried out during the last few years on clean metal surfaces. These have been obtained by‘ grinding in a very high vacuum (10 -4 to 10 -5 mm of mercury) within the body of an electron diffraction camera. The surface may be examined by diffraction immediately after preparation, and it is also possible to study the effect of the admission of controlled amounts of gas, inert or otherwise. With iron, for example, it is found that the vapours of fatty materials are adsorbed and form oriented films. On the other hand, with cerium an oxide is formed which has not hitherto been isolated (sesquioxide Ce 2 O 2 cubic). By observing the oxides and their structural changes, it is also possible to determine, in certain cases, the surface temperature developed by grinding. The author provides details of an apparatus in the course of construction under the auspices of I.R.S.I.D. (Institut des Recherches Sidérurgiques Françaises) which is to be used for extending these investigations. In particular, this apparatus contains a separate preparation chamber, so that the action of certain sulphurized compounds, especially on clean surfaces, may be studied at different temperatures.