Results found: 3

Number of results on page

Search results

Sort By:

Limit search:

CORRELATIONS OF MECHANICAL PROPERTIES AND MICROSTRUCTURE AT SPECIFIC ZONES OF WELDED JOINT OF HIGH-STRENGTH LOW-ALLOY STEELS

100%

Ivanović L., Marjanović V., Ilić A., Stojanović B., Lazić V.

Archives of Metallurgy and Materials

2018

vol. 63

issue 1

La-doped and La/Mn-co-doped Barium Titanate Ceramics

100%

Vijatović Petrović M., Bobić J., Grigalaitis R., Stojanović B., Banys J.

Acta Physica Polonica A

2013

vol. 124

issue 1

155-160

Barium titanate ceramics doped with 0.3 mol.% lanthanum and co-doped with 0.3 mol.% lanthanum and 0.05 mol.% manganese were investigated. The powders were prepared by a modified polymeric precursor method based on the Pechini process. The ceramics were obtained by sintering at 1300C for 8 h. The influence of dopants on structural changes and grain size reduction was analyzed. The presence of dopants influenced the tetragonality of the barium titanate crystal structure. Reduction of polygonal grain size with dopant addition was noticed. In the doped ceramics, characteristic phase transitions were shifted to lower temperatures in comparison with pure barium titanate. The dielectric permittivity value showed the tendency of a slight increase with lanthanum addition and further increase with adding of manganese. La as a single dopant increased the diffuseness of phase transitions indicating the formation of a diffuse ferroelectric material but in the co-doped ceramics the phase transition diffuseness decreased. The resistivity of the co-doped ceramics was higher than for lanthanum doped ceramics, indicating possible segregation of manganese at grain boundaries that influenced the total resistivity of the material.

Characterization of Barium Titanate Ceramic Powders by Raman Spectroscopy

86%

Lazarević Z., Romčević N., Vijatović M., Paunović N., Romčević M., Stojanović B., Dohčević-Mitrović Z.

Acta Physica Polonica A

2009

vol. 115

issue 4

808-810

Barium titanate, BaTiO_3 ceramic powders were prepared by mechanochemical synthesis and by the Pechini method. A powder mixture of BaO and TiO_2 was treated in a planetary ball mill in an air atmosphere for up to 1 h, using zirconium oxide vial and zirconium oxide balls as the milling medium. After 60 min BaTiO_3 phase was formed. In both ways BaTiO_3 ceramics were sintered after 2 h on 1300°C without pre-calcinations step. The heating rate was 10°C min^{-1}. The formation of phase and crystal structure of BaTiO_3 was approved by X-ray diffraction analysis and the Raman spectroscopy. The morphology and microstructure of obtained powders were examined by scanning electron microscopy method. Sharp phase transition from ferroelectric to paraelectric state was observed. The hysteresis loop is very well performed with regular sharp characteristic of ferroelectric materials.

Refine search results

2 Acta Physica Polonica A

1 Archives of Metallurgy and Materials

1 2018

1 2013

1 2009

3 Stojanović B.

1 Banys J.

1 Bobić J.

1 Dohčević-Mitrović Z.

1 Grigalaitis R.

1 Ilić A.

1 Ivanović L.

1 Lazarević Z.

1 Lazić V.

1 Marjanović V.

1 Paunović N.

1 Romčević M.

1 Romčević N.

1 Vijatović M.

1 Vijatović Petrović M.

Search results

CORRELATIONS OF MECHANICAL PROPERTIES AND MICROSTRUCTURE AT SPECIFIC ZONES OF WELDED JOINT OF HIGH-STRENGTH LOW-ALLOY STEELS

La-doped and La/Mn-co-doped Barium Titanate Ceramics

Characterization of Barium Titanate Ceramic Powders by Raman Spectroscopy