Studies On Technique And Its Application Of Ultrasonic Testing And Evaluation For Polymer Bonded Explosive

According to the engineering requirement and application of polymer bonded explosive (PBX),the physical and structural performance of PBX have been systematical studied by ultrasonic technique. Ultrasonic characteristic of PBX specimens, flaw and loosening affection on the ultrasonic characteristic of PBX have been analyzed and discussed. Ultrasonic testing stress and mechanical damage of PBX have been done. The time-frequency information on ultrasonic signals of PBX specimens has been analyzed. Time-frequency characteristic of the flaw inside PBX specimens have been distinguished. Local acoustic impedance of PBX specimens has been observed as image by scanning acoustic microscope. The structural performance of PBX specimens has been researched using the acoustic impedance image, including subsurface microstructure, characteristic of medium interface, grain form of explosive and bonded quality of PBX specimens. The results show that:1) The relationship between ultrasonic gain and thickness of PBX specimen basically assumes linearity. With the density of PBX specimens increasing, ultrasonic velocity assumes a curvilinear increase, and ultrasonic gain coefficient assumes a curvilinear decline in the range of special density. Both the crack and the loosen greatly influence the acoustic characteristic of PBX specimens, the influence of crack mainly comes from ultrasonic echo wave at the crack interface, but the influence of loosening mainly comes from grave dispersion of ultrasonic wave. With the stress of...