The Effect of Mechanical Activation on the Synthesis and Properties of Multiferroic Lead Iron Niobate
The present work studies the effect of high-energy mechanical activation using the planetary-centrifugal ball mill AGO-2 and subsequent annealing on the synthesis and magnetic properties of PbFe0.5Nb0.5O3 (PFN). This technique enables one to perform the mechanically activated synthesis of PFN at much shorter time. The results of X-ray phase analysis, electron microscopic studies and transmission Mossbauer 57Fe spectra measurement are presented and discussed. Mossbauer studies show that the temperature of magnetic phase transition in PbFe0.5Nb0.5O3 powders can be changed by mechanical activation and subsequent annealing.
Coexistence of antiferromagnetic and spin cluster glass order in the magnetoelectric relaxor multiferroic PbFe 0.5 Nb 0.5 O3.
The coexistence of cluster glass with long-range antiferromagnetic order in the relaxor ferroelectric PbFe 0.5 Nb 0.5 O3 is elucidated. While the transition at T(N) = 153 K on the infinite antiferromagnetic cluster induces 3m symmetry with large EH2 magnetoelectric response, the disconnected subspace of isolated Fe3+ ions and finite clusters accommodates the cluster glass below T(g) = 10.6 K with field-induced m' symmetry and EH-type magnetoelectric response. Critical slowing-down, memory and rejuvenation after aging, occurrence of a de Almeida-Thouless phase line, and stretched exponential relaxation of remanence corroborate the glass nature.
Metallurgical Process Engineering
The "material of choice" - steel.- Uprising of China's steel industry.- Process manufacturing industry and process engineering.- Engineering science in steel manufacturing process.- Analysis and integration of metallurgical manufacturing process.- Multi-dimensional mass flow control for metallurgical manufacturing process.- Time factors in steel manufacturing process.-Operating dynamics in the production process of steel plant.- Structure and mode of steel plant.- Steel plant and environment.