Measurement of the dynamic crack-tip displacement field using high-resolution moire photography

Martin B. Whitworth; Jonathan Mark Huntley; John E. Field

doi:10.1117/12.57499

1 December 1991 Measurement of the dynamic crack-tip displacement field using high-resolution moiré photography

Martin B. Whitworth, Jonathan Mark Huntley, John E. Field

Proceedings Volume 1554, Second International Conference on Photomechanics and Speckle Metrology; (1991) https://doi.org/10.1117/12.57499
Event: San Diego, '91, 1991, San Diego, CA, United States

Abstract

An electromagnetic device has been used to produce a planar tensile stress pulse in a plate of poly methyl methacrylate (PMMA). The pulse has a profile which is approximately square in time. It is incident on a through crack, resulting in the sudden application of a constant mode I load. This causes the stress intensity factor to increase proportionally to (loading time)^½. High resolution moiré photography is used to produce fringe patterns in real time, which are recorded with a high speed image converter camera at an inter-frame time of 2μs. The moiré technique uses a specimen grating of 75 lines mm⁻¹ which is imaged onto a reference grating of the same pitch, using optical filtering in the transform plane to double the effective frequency to 150 lines mm⁻¹. The photographs are digitized and analyzed with an automatic system based on the 2-D Fourier transform to extract one component of the displacement field to a sensitivity of approximately 1μm. This has been compared with an analytical solution for the problem.

Citation Download Citation

Martin B. Whitworth, Jonathan Mark Huntley, and John E. Field "Measurement of the dynamic crack-tip displacement field using high-resolution moiré photography", Proc. SPIE 1554, Second International Conference on Photomechanics and Speckle Metrology, (1 December 1991); https://doi.org/10.1117/12.57499

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available