Magnetic softening of young's modulus of amorphous Fe90Zr10
Abstract The Young's modulus and the internal friction of amorphous Fe90Zr10 alloy were measured near the Curie temperature using the vibrating reed technique. The modulus shows softening around Tc(= 227 K) and the internal friction undergoes drastic increase in the same temperature range. It is found that both the Young's modulus and the reciprocal of internal friction are inversely proportional to the magnetic susceptibility in the paramagnetic phase.
Elastic anomalies in iron‐platinum invar alloys
Elastic anomalies in an Fe75Pt25 single crystal have been investigated by ultrasonic pulse echo and inelastic neutron scattering measurements in the temperature range 200 to 800 K. The single crystal which was grown by the Bridgman–Stockbarger process undergoes a magnetic transition at Tc = 370 K and a martensitic transformation at Ms = 200 K corresponding to a degree of order of S=0.7. Both ultrasonics and neutron scattering reveal a softening of the transverse modes below Tc. The excess elastic constants obey an M2 law as expected from a local magnetoelastic interaction model. The longitudinal ultrasonic velocities already start to soften at 700 K whereas the neutron data for the same acoustic branch do not show any anomaly down to 200 K. The observed q dependences of the acoustic branches point towards a softening confined to the very center of the Brillouin zone.
Forced Volume Magnetostriction of Fe65(Ni1-xMnx)35 Alloys
The forced volume magnetostriction and magnetization were measured for Fe 65 (Ni 1- x Mn x ) 35 alloys with 0.05≦ x ≦0.33 at 4.2 K up to 48 kOe. With increasing x , the high field susceptibility, χ hf , increases rapidly and shows a maximum around x =0.2, where a long range ferromagnetic order disappears. The analysis of forced volume magnetostriction reveals that a rapid rise of χ hf is due to an increase of intrinsic band susceptibility around the critical concentration.