Digital X-ray Imaging Of Turbine Blade In Aero Engine

Turbine blade is the core component of aeroengine,the security and performance of the aeroengine can be directly affected by its manufacture quality.Due to the complexity of blade shape and high rate of casting defect,turbine blade must be 100%inspected by X-ray film radiography in enterprise,conventional film radiography is still the most commonly used nondestructive testing methods in domestic aviation enterprise.Digital radiography of high efficiency and lowcost is the development trend of radiographic testing in the future,therefore,it is of great significance to research the digital X-ray imaging of turbine blade.The 1st stage high-pressure turbine blade was considered as the research object,and the main research works as following:(1)Experiments research of turbine blade body was performed by computed radiography(CR)with imaging plate of IPU and IPS,CR detection process of the turbine blade body was established,and the CR image quality of a single blade body has reached the quality requirements of film radiography in enterprise.Comparative analysis shows that the imaging quality of IPU is better than IPS imaging plate.Experiments research of turbine blade body was performed by digital radiography(DR)with flat panel detector,and DR detection process of the turbine blade body was established,the DR image quality of a single blade body has reached the quality requirements of film radiography in enterprise.Experiment results show that turbine blade body can be inspected by digital radiography during an X-ray exposure.(2)Due to the complex structure of blade rabbet and the change of its thickness is big,there are serious edge etching effect,and experiments research of turbine blade rabbet was performed by CR and DR.Sodium tungstate powder was proposed to protect scattering X-ray from blade rabbet,compared with no protection,lead plate protection,sodium tungstate protection effect,and found that sodium tungstate significantly reduces scattering effect of the blade rabbet.In particular,breakthrough progress has been made in improving the quality of DR image for blade rabbet.high quality CR images and DR images of blade rabbet were obtained through experiments,and the CR and DR detection process of rabbet were established.(3)Further study on the ability of IPU to inspect multiple turbine blade body with a exposure was researched,CR detection with a exposure was carried out in asingle row of turbine blade or multiple rows of turbine blades.Test results,as long as the uniform exposure field intensity,exposure can be extended to a multiple of leaf blade body ray CR imaging,IPU imaging plate can be like a film to achieve a transillumination multiple leaf blade body,raise the efficiency of digital radiographic testing.The experimental results show that as long as the intensity of exposure field is uniform,it can be extended to a exposure with multiple blade body imaging,like the film radiography in enterprise,and the efficiency of digital X ray imaging is improved.(4)CR imaging of turbine blade body was researched using the combination of IPU and IPS imaging plate,and exposure with IPU placed above and IPS placed below.Experiment results show that the quality of front edge in blade body reach the requirements with IPS,and the quality of back edge in blade body reach the requirements with IPU.Therefore,the double imaging plate can be used to inspect the blade body in a exposure,and improved the detection efficiency.(5)The hollow turbine blade was scanned and reconstructed by industrial CT,CT images of blade structure were obtained,three-dimensional visualization analysis of internal defects and wall thickness measurement was performed.