New method for analysis of gas content in solid materials and coatings has been developed. The method is based on a complex mechano-physico-chemical phenomenon of emission of neutral molecules stimulated by mechanical activation of material, i.e. friction, rolling, indentation, tension and other.
Gases absorbed, e.g. hydrogen and helium, can be analyzed using this method in both bulk or coating of the material. The sensitivity of the method is below 10 ppm of atomic concentration, while spatial resolution in 2D and 3D analysis is lower than 1 micrometer.
The effect of adsorption and readsorption of emitted gases on accuracy and sensitivity of the measurement by this method is studied theoretically. The number of readsorbed molecules can be as high as 10% of the total number of emitted molecules, and the percentage depends on the adsorption characteristics of the surfaces, geometry of a vacuum system and residual pressure. Readsorption of gases on the sample surface is specially addressed since it can produce significant systematic error of the measurement. The value of this error was determined as function of residual pressure.
In addition, dynamic range of the method is studied theoretically and experimentally. Experimental validation of the method was done using normal and deuterated stainless steel samples and various hard coatings including boron carbide, amorphous carbon, nanostructured copper and other.
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