Metastable magnetic behavior in La0.9Tb0.1MnO3

Abstract

The linear and nonlinear magnetizations of La 0.9 Tb 0.1 MnO 3 at low temperatures were reported in detail. The temperature dependence of magnetization shows peaks at 50, 100 and 150 K, respectively. When LaMnO 3 is Tb-doped, its magnetic structure exhibits a canted antiparallel spin order. This is different from classical antiferromagnetic (AFM) in which the relaxation behavior takes place at about 150 K. At 50 K, Tb-doped LaMnO 3 exhibits canonical spin glass behavior, arising from the competition of exchange and super-exchange between spins. The peak at 100 K shows neither spin glass behavior nor canted AFM behavior. Its peak value increases with frequency increasing, and the transition temperature of the peak shifts to higher temperatures with frequency increasing. The study of aging behavior at 100 K shows a periodical variable metastability, which is ascribed to the competition between ferromagnetic (FM)-, AFM-and sinusoidal-order interactions. This work should shed a light on understanding the complex magnetic structure of the perovskite oxides.

Deformation Behavior and Microstructural Evolution of Zr–Sn–Nb–Fe Alloy over a Wide Temperature Range Based on the Law of Mixture

“…The constitutive model of the α phase in the temperatures range of 973-1173 K is modified by the coefficient of W, and the material constants expression of the final constitutive model of the α phase is obtained according to Equation (7), which is expressed as Equation ( 17), and its coefficients are shown in Table 3.…”

“…The recrystallization temperature of Zr–Sn–Nb–Fe alloy is near 873 K, and the beginning of α→β is about 883 K. [ 7,8 ] During the deformation process, the alloy often exhibits hardening or softening phenomena (work hardening, dynamic recrystallization, dynamic recovery, etc.). Constitutive model is one of the methods to describe material flow stress.…”

Development and Property Tuning of Refractory High-Entropy Alloys: A Review

“…Usually, the oxide film is formed on the metal surface during the oxidation process of the alloy. However, only in the oxide film with stable chemical properties, denseness, and fewer defects, a trivial difference in thermophysical parameters with the matrix and good combination can hinder the further oxidation of the alloy and protect the matrix [101,102].…”

Development of Enameling Steel Sheet Used for Heat-Exchanger

“…It can be inferred that more oxygen content in steel should be beneficial to the element diffusion between steel and enamel and thicker transition layer with stronger bonding force could be formed during enameling process, which need to be verified in future research. (4) The pin-hole defect results from the carbon monoxide gas generated during enameling heating [7]. The content of carbon is controlled less than 0.0050% and the element niobium also have a good effect on binding carbon atoms, so the steel has good pin-hole resistance.…”