RADIATION METHOD FOR MEASUREMENT OF DENSITY Russian patent published in 1996 - IPC

FIELD: densimetry of solids by backward spattering of fast-moving electrons by means of powder metallurgy method. SUBSTANCE: flow of electrons is directed to surface of object and backward scattered electrons beyond screened area of object surface are recorded; energy of electrons and sizes of screened area are increased stepwise; results of recording for object under test and for model specimens are obtained for each kind of energy; density of depth layer of object is judged from results of recording. Backward scattered electrons escaping from any point of surface are additionally recorded; energy of electrons in beam is increased stepwise in accordance with mass thicknesses of layers of standard object; results of recording at each energy are obtained for object under test and for model specimen which is made taking into account the results of recording backward scattered electrons escaping from any point of surface, as well as the results of recording the backward scattered electrons beyond screened areas at all previous kinds of energy both for object under test and for model specimens, as well as in kind of materials of layers and order of their sequence in depth of object. EFFECT: possibility of measurement of distribution of density in underlayers of objects under test which consist of layers whose atomic number, average density and average thickness are known. 14 dwg