Method for positioning and quantifying ultrasonic inspection defects of billets

The invention relates to a method for positioning and quantifying ultrasonic inspection defects of billets and belongs to the field of inspection and detection. The method comprises the following steps: classifying abnormal waveform states of large/medium-sized cylindrical extrusion billets or electroslag ingots in a contact-method ultrasonic longitudinal wave testing process, fully considering the similarity of diameters of acoustic beams and acoustic transmission performances of materials, and respectively positioning and quantifying the defects. The technical problem that the conventional defect positioning and quantifying method is not applicable is solved, and a reliable basis is provided for subsequent treatment of the billets.