| 摘要 |
PURPOSE:To enable the non-destructive testing of mechanical properties of a ferromagnetic material, by performing magnetomechanical acoustic analysis. CONSTITUTION:A material 10 to be measured is placed so as not to be contacted with an electromagnet 12 and the change in the intensity of an external magnetic field from a demagnetized state to a state near to a saturated magnetized state is imparted by an AC power source 13 while the magnetomechanical acoustic discharge MAE amount of an acoustic detection sensor 14 is treated by an effective voltmeter 18, a digital wave form memory apparatus 22 and a wave form detector 20 to calculate the relation of the intensity of the external magnetic field and the MAE amount. Line parts B1- B6 correspond to a characteristic parameter B and to peak values are present in a MAE wave form when the intensity of the external magnetic field is made constant and corresponds to a characteristic parameter A. There is mutual relation between thus calculated parameters A, B and a toughness value and a strength value. Therefore, the parameters A, B are outputted from the apparatus 22 and, at the same time, processed by an operation processing device 24 and subjected to digital display as the toughness value and the strength value by a display apparatus 26 and recoded to recording paper by a recording apparatus 28. |
