Dual-frequency Eddy Current Non-destructive Detection of Fatigue Cracks in Compressor Discs of Aero Engines

Abstract

Eddy current non-destructive testing is used to inspect the critical aircraft components. The shortcomings of the inspection method identified, based on a few accidents, necessitate the development of high sensitive and reliable testing procedures for inspecting the critical safety related aircraft components. This paper discusses a dual-frequency eddy current testing procedure developed for inspection of compressor discs of aero engines for detecting fatigue cracks with high sensitivity and reliability. This procedure is capable of detecting fatigue cracks smaller than 2 mm in comparison to 4 mm cracks that can be detected with the currently practiced eddy current testing procedure.