Simulation And Verification Of Radiography Testing Of Aerial Precision Castings

Aerial precision castings were big, complex and with some cavity. A largenumber of test shots were needed in order to avoid residual error when testing thesecastings by using traditional radiography. Ray computer simulation, as a low costingand convenient technology, simulates actual transillumination process rapidly andprovides reference data for real transillumination. Therefore this technology hasbecome one of the best assistant of traditional X-ray testing process.Complex aerial precision castings were studied in this thesis. Correction factor ofdensity from XRSIM ray simulation software were tested and revised. Densityresolution, spatial resolution and other analytic function of sensitivity in XRSIM weretested as well. Combination of an experimental measurement and software simulationto correctthe blackness of simulation software, Guarantee the software simulation ofimage blackness values adjusted to the same as the actual detection of the film, Andmaking the series of three-dimensional map of the flat-panel hole type IQI,andimportit into the software. The experiments show the contrast sensitivity of the softwaresimulation image can be achieved2-2T. For Aviation Precision casting structure iscomplex and difficult to detect problems, Identified the method by computer-raydetector simulation technology to guide the work thinking and working process ofactual component testing. And proposed double film, change-ray incident angle andchange-ray voltage to eliminate the undetected area. Effectively improve the detectionsensitivity, the comprehensive implementation of the computer simulation design ofthe plate of the precision casting.Results show that based on optical tracking technology and ray attenuationtheory, RSIM ray simulation software with ideal detector has characters as follows:convenient to input tested objects, precise to show density when correction factor ofdensity was taken, accurate to simulate density resolution and spatial resolution,reasonable to optimize exposure parameters, accurate to calculate dead or lowsensitive zone of different position in incidence direction. Transillumination positionwas optimized by the software. Real radiograph of aerial precision castings, guided bythe software, has meet requirements of ASTM E192Standard Reference RadiographsFor Investment Steel Castings of Aerospace Applications and also meet requirementsof testing castings in production.Thesis research results will reduce thenumber of real radiograph，reduce designcosts, Improve the reliability of design,lay the foundation for digital design and digitaldetection, reduce pollution and realize green manufacturing. Results will be usedwidely in the field of X-ray testing.