Evidence of magnetostrictive influence on magnetic hysteresis behaviour at low temperature

Magnetic materials with very different saturation magnetostriction (lambda(s)) were selected: Co59Fe16Zr6CU1Nb2B16 amorphous alloy with low lambda(s) value (congruent to 10(-7)), Fe62.5Co6Ni7.5Zr7.5Cu1Nb2B15 amorphous alloy with lambda(s) congruent to 10(-5) and Tb0.27Dy0.73Fe2.0 (Terfenol) alloy with giant magnetostriction (lambda(s) congruent to 10(-3)). Magnetization intensity curves were obtained by means of a vibrating sample magnetometer from room temperature to 10 K. At low magnetizing field a reentrant magnetization behaviour was evidenced in all the investigated materials. This effect is proportional to magnetostriction value, going from a large effect in Terfenol to a small one in low magnetostriction materials. Saturation field, coercive field and hysteresis area behaviours as a function of temperature are in agreement with both the measured magnetization reentrance and stress-induced effects.