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Finite Element Models of PAUT Inspection of Fatigue Cracks

Project Code: 0901-09


Validate finite element models (against previous validation results and experiment) of ultrasonic techniques using phased array beams for the detection of small planar flaws representing fatigue cracks.

Project Outline

Stage 1: Determine limits of model validity for unfocussed single crystal UT of small smooth planar flaws by comparing the predicted signal amplitude with a known theoretical benchmark. This stage will demonstrate the feasibility of FE models for the detection of small defects and optimise the finite element parameters (such as mesh size and number of mesh elements) to reach sufficient accuracy within acceptable time frames.

Stage 2:
Compare results from FE models of unfocussed single crystal UT for detection of crack-like slots representing small fatigue cracks with experimental evidence. The slots will be of various depth sizes and tilts (misorientation with respect to the sound beam).

Stage 3: Evaluate the phased array sound beams using the FE model and validate against evidence generated in the CRP project 15030. This is a critical stage to ensure that (1) the FE package is capable of modelling phased array transducers, (2) the process is not too complex/time consuming and (3) the sound field is valid. If sound field prediction is sufficiently accurate, the interaction of the sound field with small fatigue-like defects will be modelled using the FE package and validated against phased array experimental evidence, similar to Stage 2.

Relevant Industry Sectors

Power Generation, Oil and Gas, Aerospace

Technical and Economic Benefits

This project addresses requirements of Research Theme SINDT-5. The in-service failure of critical components due to fatigue cracks can have serious economic and safety implications to the operators, workers and the environment. The present project aims towards the better design of advanced ultrasonic inspection techniques to detect and characterise very small planar cracks, such as fatigue cracks.


Industrial Member Reports

Access the Industrial Member Report resulting from this programme:

Evaluation of the FEA package PZFlex for the ultrasonic beam profile and response on smooth fatigue cracks

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