The invention belongs to the technical field of
nondestructive testing, and relates to a method for ultrasonic distinguishing of an R-region defect of a
composite material structure. The method for ultrasonic distinguishing of the R-region defect of the
composite material structure and a method for determining the depth position of the detected defect are constructed by utilizing the
signal relationship between changes of
time domain amplitude, phase position and
propagation time as well as other parameters and the inside of an R-region
skin, the interface between the R-region
skin and an R-region filling area, the R-region filling area and the defect thereof of the detected
composite material structure based on
broadband narrow pulse ultrasonic reflection signals from different directions and positions of the R-region of the detected composite
material structure and characteristics thereof; and the ultrasonic RF and imaging detection of the R-region of the composite
material structure can be realized by adopting a soft membrane contact
coupling or water-spray
coupling, manual or automatic scanning mode, and the detecting thickness range of the R-region is 0.5-20mm. Actual detection results indicate that the accuracy and the reliability for distinguishing of R-region
ultrasonic detection defects of the composite
material structure, as well as the defect detection capability and the detectability for the R-region can be remarkably improved.