Non-Destructive Inspection Methods for Propulsion Systems and Components.

摘要

The safety in use of mechanical systems is dependent on the identification of possible defects in their component parts. This particularly applies to turbine engines, certain components of which, especially turbine and compressor discs and blades, are subjected to particularly severe stresses; creep, low cycle fatigue, thermal fatigue. These potential defects must be detected, on the one hand when the parts are at the manufacturing stage and, on the other, during periodic inspections in service. It is, therefore, essential to have available non-destructuve inspection methods which, while they are accurate and sensitive, can be used in the workshop for the detection of even minor defects and cracks. A considerable amount of research work has been done throughout the world in this field and has led to the development of various methods; ultrasonic, magnetometer, X-ray. New procedures, which are complementary to these now conventional methods, are in process of development or optimization; acoustic emission, laser holography, eddy current etc. The aim of this Lecture Series is to survey the means currently available, with particular emphasis on the intrinsic possibilities and present limitations of the non-destructive inspection methods most widely applied to turbine engines, and to describe the state of progress of research on more recent methods.