AN ULTRASONIC NONDESTRUCTIVE TEST PROCEDURE FOR THE EARLY DETECTION OF FATIGUE DAMAGE AND THE PREDICTION OF REMAINING LIFE

The goal of nondestructive testing may be simply expressed as the detection and complete specification (size, shape, orientation, and so on) of flaws. This is seldom possible, however. The most dangerous flaw is one that is crack-like or that serves as a crack initiation site. A procedure to detect and estimate fatigue damage occurring at such a site is reported. A computer-based data acquisition system is used to analyze data from 2024-T4 A1 fatigue specimens containing a through hole. Specimens are fatigue loaded to produce a spectrum of damage levels and interrogated using a simple contact 10 MHz shear wave system. Features selected from the signal amplitude-time, spectrum, and cepstrum signatures-are used in a computer learning network to make an early detection of fatigue damage and a quantitative prediction of remaining life. A scanning microscope is used to examine the damage at the limit of detection. Fatigue damage was sensed with 92 percent success after 10 percent of specimen life. Estimates of damage were made within plus or minus 20 of the actual fatigue life percentage for 76 percent of the data.

  • Availability:
  • Corporate Authors:

    American Society for Nondestructive Testing

    914 Chicago Avenue
    Evanston, IL  United States  60202
  • Authors:
    • Carson, J M
    • Rose, J L
  • Publication Date: 1980-4

Media Info

  • Features: References;
  • Pagination: p. 27-34
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00314964
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Aug 27 1980 12:00AM