Effect of stress annealing on Galfenol and Alfenol magnetostrictive alloys

A. E. Clark; J. B. Restorff; M. Wun-Fogle; Eric Summers

doi:10.1117/12.657980

6 April 2006 Effect of stress annealing on Galfenol and Alfenol magnetostrictive alloys

A. E. Clark, J. B. Restorff, M. Wun-Fogle, Eric Summers

Proceedings Volume 6170, Smart Structures and Materials 2006: Active Materials: Behavior and Mechanics; 61700I (2006) https://doi.org/10.1117/12.657980
Event: SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring, 2006, San Diego, California, United States

Abstract

Galfenol (Fe100-xGax, x = 6, 12.5, 17, 18.4, 19, 22) and Alfenol (Fe81Al19) alloy rods (~50 mm x 6 mm dia.) were annealed under compressive stresses up to 219 MPa at temperatures from 100°C to 700°C for 10 to 100 minutes. Because of the magnetostriction of the alloys, these heat treatments build in a uniaxial magnetic anisotropy that depends upon annealing stress, annealing temperature, and alloy composition. This built-in uniaxial magnetic anisotropy extends the high power capability of these alloys to operate both in tension and in compression. Magnetization and magnetostriction measurements of both unannealed and annealed alloys were taken from −100 MPa to +40 MPa. To fit the magnetization and magnetostriction as a function of magnetic field and stress, an energy expression containing a fourth order anisotropy term (cubic term) plus a second order uniaxial term was utilized. The computed magnetizations and magnetostrictions are found by an energy-weighted average using the Armstrong smoothing constant. Excellent fits to the magnetostriction and moment data were obtained. From the model fits m, d33 and k33 were calculated. Since the built-in stresses can be found simply from the model, it is possible to predict the amount of prestress built into the alloys.

Citation Download Citation

A. E. Clark, J. B. Restorff, M. Wun-Fogle, and Eric Summers "Effect of stress annealing on Galfenol and Alfenol magnetostrictive alloys", Proc. SPIE 6170, Smart Structures and Materials 2006: Active Materials: Behavior and Mechanics, 61700I (6 April 2006); https://doi.org/10.1117/12.657980

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