Accession Number:

ADA001621

Title:

A Laser Interferometric Technique for Crack Surface Displacement Measurement,

Descriptive Note:

Corporate Author:

AIR FORCE MATERIALS LAB WRIGHT-PATTERSON AFB OHIO

Personal Author(s):

• Sharpe,William N. , Jr.
• Grandt,Alten F. , Jr

Report Date:

1974-07-01

Pagination or Media Count:

33.0

Abstract:

The opening of a fatigue crack in an aluminum specimen was measured by optical interference from single grooves ruled on both sides of the crack. Displacement can be measured with a sensitivity of 0.1 micron, making the technique particularly useful in studies of crack closure. Details of this easy, inexpensive technique are discussed in this report.

Descriptors:

• *TEST EQUIPMENT
• *FRACTURE(MECHANICS)
• *ALUMINUM
• MEASUREMENT
• NONDESTRUCTIVE TESTING
• LASERS
• INTERFEROMETRY
• CRACK PROPAGATION
• FATIGUE(MECHANICS)

Subject Categories:

• Metallurgy and Metallography
• Test Facilities, Equipment and Methods

Distribution Statement:

APPROVED FOR PUBLIC RELEASE