Nondestructive testing system and method for turbine disc by using bilinear array transducer

Abstract

The invention discloses a nondestructive testing system and method for a turbine disc by using a bilinear array transducer. The detection system is used for processing an image formed by ultrasonic echo data acquired by the bilinear array transducer by using a computer in which a Space-Defect method is stored so as to obtain a defect-imaging point on a tested object. According to the method, the Space-Defect method is adopted to solve the problem that a conventional phased array is difficult to solve the characteristic of small defects smaller than half wavelength, the Space-Defect method can achieve high-precision automatic recognition and high-precision imaging of a test piece of a complex structure, and a new way is provided for detection of diffusion welding area type defects of the aviation high-temperature alloy disc.

Description

technical field [0001] The invention relates to the technical field of non-destructive testing, and more particularly refers to a non-destructive testing that can be performed on a turbine disk with a narrow gap. Background technique [0002] A transducer is an energy conversion device, and its performance description and evaluation require many parameters. The characteristic parameters of the transducer include resonance frequency, frequency bandwidth, electromechanical coupling coefficient, electroacoustic efficiency, mechanical quality factor, impedance characteristic, frequency characteristic, directivity, emission and reception sensitivity, etc. Transducers for different purposes have different requirements on performance parameters. For example, for transmitting transducers, the transducers are required to have large output power and high energy conversion efficiency; for receiving transducers, wide Frequency band and high sensitivity and resolution, etc. Therefore, ...

AI Technical Summary

Problems solved by technology

Aeronautical superalloy discs work under extreme conditions such as high speed, high load, high temperature, and high pressure for a long time. The weld zone is a stress concentration area. When defects occur, area defects such as micro-close gaps and microscopic distribution appear on the diffusion welding interface. Become a major safety hazard affecting the performance of aero-engines

The detection scheme based on the conventional single probe has the disadvantages of low detection resolution, low acoustic energy, and low imaging resolution. Therefore, it is of great practical significance to establish a detection method suitable for area-type defects of diffusion welding of superalloy disks.

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