| 摘要 |
<p>The sound velocity (V) of a cast iron test object is measured by ultrasonic. The sound velocity of this test object and the sound velocity (Vm) of a given metal corresponding to the test object are compared to obtain a sound velocity ratio (V/Vm). This ratio is converted to the required physical quantity (such as a graphite spheroidizing ratio, a state classification, a tensile strength, and an elongation percentage) by an empirical formula and others (530) regarding the sound velocity ratio, thus calculating the physical characteristic value of the foregoing test object. It is, therefore, possible to measure or calculate the analytical value and characteristic value of the cast iron structural state easily without any destruction.</p> |
