Microstructure control for developing Fe–Pd ferromagnetic shape memory alloys

✍ Scribed by H.Y. Yasuda; N. Komoto; M. Ueda; Y. Umakoshi

• Book ID: 104438311
• Publisher: Institute of Physics and National Institute of Materials Science
• Year: 2002
• Tongue: English
• Weight: 278 KB
• Volume: 3
• Category: Article
• ISSN: 1468-6996
• DOI: 10.1016/s1468-6996(02)00012-8

✦ Synopsis

The effect of microstructure on the ferromagnetic shape memory effect in Fe±Pd alloys was examined focusing on the orientation distribution, the grain boundary character and the grain size. Fe±29.7±31.0 at.%Pd polycrystals composed of columnar or equiaxed grains were prepared and their magnetostriction was measured under a magnetic ®eld up to 10 kOe. The magnetostriction of the columnar crystals was much larger than that of the equiaxed ones due to the development of k100l ®bre texture and k100l tilt grain boundary. In particular, a large magnetostriction of 4.5 £ 10 24 was obtained even in the polycrystals. The grain boundaries of the columnar crystals also in¯uenced the variant selection of martensites, resulting in strong dependence of the magnetostriction on the direction of magnetic ®eld. Larger grain size did not always result in larger magnetostriction in Fe±Pd alloys. An increase in the grain size of the alloys was sometimes accompanied by the development of several sets of twin variants within a grain, resulting in a decrease in the magnetostriction.