Detection of Weak Bond-lines in Solid Rocket Motors Using a Ultrasonic Technique

PDF

Authors
  1. Sinclair, A.N.
  2. Safavi, V.
  3. Jastrzebski, M.
Corporate Authors
Defence R&D Canada - Valcartier, Valcartier QUE (CAN);Toronto Univ, Toronto ONT (CAN) Dept of Mechanical Engineering;Toronto Univ, Toronto ONT (CAN) Dept of Industrial Engineering
Abstract
Poor bonding between the rubber liner and solid propellant used in rocket motors can lead to failure of the motor. An ultrasonic nondestructive testing method to detect weakness at this interface is required. In this preliminary study, the following goals were set: (1) Measure the ultrasonic properties of the rubber liner in order to provide the necessary data for further investigation of a feasible technique. (2) Perform preliminary ultrasonic tests and compare ultrasonic signatures on "good" and "bad" areas of an analog solid propellant rocket motor manufactured for this study. The first objective was successfully completed, and showed that shear wave attenuation coefficients are extremely high in the rubber. As a result, only compression waves are practical for ultrasonic testing of solid rocket motors. Compression waves were capable of distinguishing good bonds at the liner/propellant interface from a total debond. Due to difficulties in securing an experimental specimen with known intermediate bond qualities, it was not possible to demonstrate whether weakened interfaces could be ultrasonically distinguished from a good interface. A specialized laboratory setting may be needed for ultrasonic testing of these rocket motors, based on the high sensitivity of results to the test parameters.

Il y a un résumé en français ici.

Keywords
Debond;Time-domain;Frequency domain;Weak bond;Longitudinal wave;Shear wave;Attenuation;Inert propellant;Rubber liner;Steel case;Dispersive media
Report Number
DRDC-VALCARTIER-CR-2004-006 — Contractor Report (Final)
Date of publication
11 Feb 2004
Number of Pages
48
DSTKIM No
CA023793
CANDIS No
521187
Format(s):
Hardcopy;Document Image stored on Optical Disk

Permanent link

Document 1 of 1

Date modified: