| 摘要 |
PROBLEM TO BE SOLVED: To clearly discriminate an in-steel inclusion from porosity using a result of ultrasonic flaw detection. SOLUTION: This method is provided with a process for sampling a test piece of steel of an evaluation object from a steel material provided by press-forging a cast piece at≥6 press-forging ratio, a process for detecting nonmetallic inclusion existing in the test piece using a submerged ultrasonic flaw detection method, and a process for evaluating the inclusion in the steel based on a result in the detecting process. A defect existing depth is found to discriminate the inclusion from the porosity based on the center frequency, in the inclusion evaluating process. COPYRIGHT: (C)2004,JPO
|
