The Devil and the Surfaces

Author:  Michel Cardon
Source:  The Shot Peener magazine, Vol 20 / Issue 3, Summer 2006
Doc ID:  2006027
Year of Publication:  2006
Abstract:  
Michel Cardon is retired from the vacu-blast industry and resides in Paris, France. During his career, he was the manager of the vacu-blast department of his family business, Satem. He formed Matrasur which was later purchased and became Wheelabrator. Some of his career highlights include being a guest of the U.S. Capitol in 1982 and a meeting with Jacques Chirac. The eminent physicist, Wolfgang Pauli, used to say, "God made the bulk; the surface was invented by the devil." Pauli explained that the diabolical characteristic of surfaces was due to the simple fact that a solid surface shares its border with the external world. Inside the solid, each atom is surrounded by other similar atoms. Surface atoms may interact either with other atoms from the same surface, or with atoms located just below or just above it, or with atoms located beyond it. Therefore, surface properties of a solid are quite different depending upon one's location. As an example, surface atoms' minimal energy spatial pattern is often quite different from internal atoms' minimal energy spatial pattern. Surface structures are complex, and for a long time, every effort made to establish precise experimental and theoretical descriptions of these structures failed. The surfaces of parts are the location for many phenomena between the material and its environment, where all physical and chemical interactions and exchanges take place. A part's surface is quite often associated with a useful function-it might be absorbing, reflecting, supporting, insulating, conducting. . . Because the processes used to manufacture, treat, protect, coat, or assemble part's surfaces will determine the service life for the part, surface treatments have a tremendous importance in industry. Yet, partly because of historical reasons, they were, and sometimes still are, underestimated.