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Simulating the X-Ray Image Contrast to Set-Up Techniques with Desired Flaw DetectabilityThe paper provides simulation data of previous work by the author in developing a model for estimating detectability of crack-like flaws in radiography. The methodology is being developed to help in implementation of NASA Special x-ray radiography qualification, but is generically applicable to radiography. The paper describes a method for characterizing X-ray detector resolution for crack detection. Applicability of ASTM E 2737 resolution requirements to the model are also discussed. The paper describes a model for simulating the detector resolution. A computer calculator application, discussed here, also performs predicted contrast and signal-to-noise ratio calculations. Results of various simulation runs in calculating x-ray flaw size parameter and image contrast for varying input parameters such as crack depth, crack width, part thickness, x-ray angle, part-to-detector distance, part-to-source distance, source sizes, and detector sensitivity and resolution are given as 3D surfaces. These results demonstrate effect of the input parameters on the flaw size parameter and the simulated image contrast of the crack. These simulations demonstrate utility of the flaw size parameter model in setting up x-ray techniques that provide desired flaw detectability in radiography. The method is applicable to film radiography, computed radiography, and digital radiography.
Document ID
20150002990
Document Type
Presentation
Authors
Koshti, Ajay M.
(NASA Johnson Space Center Houston, TX, United States)
Date Acquired
March 16, 2015
Publication Date
March 11, 2015
Subject Category
Instrumentation And Photography
Quality Assurance And Reliability
Report/Patent Number
JSC-CN-32914
Meeting Information
SPIE Smart Structures/NDE 2015(San Diego, CA)
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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