| 摘要 |
PURPOSE:To measure the thickness of each metal in metal plates and the like wherein different metals are stuck without destruction, by performing gamma ray detection by using M ossbauer effect. CONSTITUTION:The laminated plates are formed by sticking a metal plate 1 to a metal 2 which is differenct or similar to the metal plate 1. A gamma ray source 4 which has an excited isotope of the metal which is contained in the metal 1 or 2 is provided to face the laminated plate. when the gamma rays, which are emitted by the excited state of the isotope A, are irradiated on the element A in unexcited state, the element A is resonated with the gamma rays and a bsorbs and scatters the gamma rays in every direction. This is called the M ossbauer effect. Thus the gamma rays are emitted from the laminated plate 1. When collimators 3 and 5 are arranged as shown in the Figure, and the collimator 5 is moved in parallel with the plate 2, a detector 6 detects the gamma rays when the central axis line of the collimator is located between points E and F. The thickness of the plate 1 is obtained from the operating position of said detector 6. |
