Principles and Application of Magnetic Rubber Testing for Crack Detection in High-Strength Steel Components: I. Active-Field Inspection
Abstract
Magnetic rubber testing (MRT) is a sensitive non-destructive inspection technique, capable of detecting cracks as small as 0.5 mm (0.020 inch) in length with high reliability. Since its introduction in the 1970s, MRT has been successfully used to inspect high-strength steel aerospace components for surface-breaking fatigue cracks. However, despite its widespread use and apparent simplicity, the underpinning science of MRT is not highly developed. In response to some uncertainties regarding potential unreliability in the application of MRT for certain test conditions, the scientific principles governing both active-field and residual-field variants of MRT were examined. The results of theoretical and experimental investigations into active-field MRT are documented in the current report, which describes the principles of active-field MRT, and then examines both the basis for verification of adequate applied field strength for D6ac steel and the effect of the perpendicular versus tangential components of applied magnetic field on inspection reliability. The results of related study into residual-field MRT are presented in a companion DSTO report.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 2014
- Accession Number
- ADA620200
Entities
People
- G. R. Hugo
- M. E. Ibrahim
- S. K. Burke
Organizations
- Defence Science and Technology Group