Phase and morphology investigation of BaxSr1−xTiO3 (x=0.6, 0.7 and 0.8) powders

Structural and mechanical properties characterization of barium strontium titanate (BST) ceramics

“…Furthermore, this ratio is increased for each specimen upon increasing of sintering time, indicating that the particle size is decreased, as seen in Fig. 5, where the intensities of the diffraction peaks are decreased which is in good agreement with the reported result [34]. Microstructures of Ba x Sr 1-x TiO 3 ceramics, with x=1, 0.7, 0.6, and 0.5, were described [37], and the reported results showed an abnormal grain growth obtained with coarse grains of about 50 μm, surrounded by fine grains of about 2 μm.…”

“…As can be seen, a similar behavior, to that of Ref. [33], has been obtained for all tested specimens where ρ is increased for each composition with increasing of sintering time from 2 to 10 h. Therefore, the increase in density with the increase of sintering time in the range 2-10 h could be attributed to shrinkage in these ceramics [33,34].…”

“…It has been well known that crystallinity of BST ceramics is improved by increasing of calcining or sintering temperature. Referring to the reported XRD data on BST ceramics [28,34], lattice parameters were found to increase with increasing of calcining temperatures from 1200 to 1400°C for each Sr content. Also, an increase in Sr content was accompanied by a decrease in lattice parameters and particle size, was reported as well.…”

“…Secondly, domain mobility Table 2 Lattice parameters, a, c, the ratio (c/a), and the particle size of Ba (1-x) was restricted at lower temperatures due to pinning of the domain boundaries by crystal defects, which became easier upon increasing of calcining temperatures, leading to an increase in the particle size. Bearing in mind, these interpretations were proposed when Ba replaced Sr in Ba (x) Sr (1-x) TiO 3 ceramics [34]. Thus, the converse action of the above assumptions will be in favor of our results on Ba (1-x) Sr (x) TiO 3 ceramics, i.e., (c/a) ratio is decreased upon increasing of Sr, at the expense of Ba, and increases with sintering time, for same Sr content, as confirmed by Scherrer's particle size results, see Table 2.…”

“…Also, an increase in Sr content was accompanied by a decrease in lattice parameters and particle size, was reported as well. Two interpretations were proposed [34], firstly, at low calcining temperatures the powders existed in a more strained form with the atomic entities in nonequilibrium positions which relaxed to equilibrium at higher temperatures, and thus lattice parameter were increased. Secondly, domain mobility Table 2 Lattice parameters, a, c, the ratio (c/a), and the particle size of Ba (1-x) was restricted at lower temperatures due to pinning of the domain boundaries by crystal defects, which became easier upon increasing of calcining temperatures, leading to an increase in the particle size.…”