NEW TECHNIQUES IN NONDESTRUCTIVE TESTING (EXO-ELECTRON EMISSION PHASE). PART 1.

A direct connection exists between the fatigue damage in a metal and thermally induced post-fatigue exo-electron emission. This effect is due to the migration of vacancies to the surface. Exo-electron emission can be used to measure fatigue in structures, and monitor annealing of quenched metals. The investigation followed the growth of 'tearing' failures in various metals. The technique can be extended to detection and monitoring of fatigue crack growth. Apparatus for applying these techniques to structures in-the-field has been designed and is being constructed and tested.(Author)

• Supplemental Notes:
  • ARPA Order-1244.
• Corporate Authors:

  University of Arizona, Tucson

  Engineering Experiment Station
  Tucson, AZ  United States 
• Authors:
  • Hoenig, S A
  • Ott, W A
  • Ali, M T
  • Russell, T A
• Publication Date: 1971-12

Media Info

• Pagination: 44 p.

Subject/Index Terms

• TRT Terms: Cracking; Fatigue cracking; Fatigue strength; Nondestructive tests
• Uncontrolled Terms: Crack propagation
• Subject Areas: Marine Transportation; Materials;

Filing Info

• Accession Number: 00041461
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: AFML-TR-71-140-Pt- 1Tech Rpt
• Contract Numbers: F33615-68-C-1707
• Files: TRIS
• Created Date: Mar 2 1973 12:00AM