Piezomagnetic Constant Variations in Galfenol Alloys Due to Sample Mounting and Alloy Preparation
Abstract
This document reports on the results of the characterization of three varieties of Galfenol-18.4 (Fe81.6Ga18.4) and Galfenol-18.4 steel rods. Galfenol steel has a small portion of the iron replaced by low carbon steel. This adds small amounts of carbon as well as small amounts of the tramp elements contained in the steel. Rods were grown by free standing zone melt (FSZM) or an advanced Bridgman (AB) technique. Magnetic induction B and strain S were measured as a function of magnetic field H at constant stresses of -27.6, -55.2, and -82.7 MPa. The piezomagnetic constants d33 and mu33 varied in shape and size not only due to composition, but also among similar samples and different mountings of the same sample in the experimental appartus. Surprisingly, the largest variations due to mounting occurred in the samples with the highest d33's. Both the d33 and mu33 data were fit to Gaussians. Comparisons of data andmodel S-H curves are presented. The B-H hysteresis was 1100+- 100 J/m3 for all of the samples.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 2015
- Accession Number
- AD1068054
Entities
People
- Eric Summers
- James B. Restorff
- Marilyn Wun-fogle
Organizations
- Naval Surface Warfare Center Carderock Division