Effect of processing parameters on microstructural properties of lead magnesium niobates

被引：18

作者：

Bhakar, Ashok ^{[1
,2
]}

Pandey, Adityanarayan H. ^{[2
,3
]}

Singh, M. N. ^{[1
]}

Upadhyay, Anuj ^{[1
]}

Sinha, A. K. ^{[1
,2
]}

Gupta, S. M. ^{[2
,3
]}

Ganguli, Tapas ^{[1
,2
]}

Rai, S. K. ^{[1
]}

机构：

[1] Raja Ramanna Ctr Adv Technol, Synchrotrons Utilizat Sect, Indore 452013, Madhya Pradesh, India

[2] Homi Bhabha Natl Inst, Training Sch Complex, Bombay 400094, Maharashtra, India

[3] Raja Ramanna Ctr Adv Technol, Laser Mat Sect, Indore 452013, Madhya Pradesh, India

来源：

ACTA CRYSTALLOGRAPHICA SECTION B-STRUCTURAL SCIENCE CRYSTAL ENGINEERING AND MATERIALS | 2017年 / 73卷

关键词：

microstructural analysis; polar nanoregions; Rietveld method; powder diffraction; lead magnesium niobate; relaxor ceramic; X-RAY-DIFFRACTION; SUBSOLIDUS PHASE-EQUILIBRIA; DIELECTRIC-PROPERTIES; RELAXOR FERROELECTRICS; REACTION CHEMISTRY; CRYSTAL-STRUCTURE; PEROVSKITE; PMN; TRANSITION; SCATTERING;

D O I：

10.1107/S2052520617012872

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The synchrotron powder X-ray diffraction (XRD) and subsequent detailed Rietveld analysis of lead magnesium niobate (PMN) samples were performed to study the microstructural properties of polar nanoregions (PNRs) of the R3m phase. PMN samples were synthesized under different sample processing conditions. The line profile broadening analysis of room-temperature synchrotron powder XRD patterns was performed using the multi-phase Rietveld refinement method for isotropic microstructural evaluation of different PMN samples. The two phases of perovskite PMN considered in the Rietveld refinement approach for satisfactorily fitting the XRD patterns are the paraelectric cubic phase (Pm (3) over barm) and the local rhombohedral phase (R3m) which corresponds to the PNRs. It is observed that the contributions of the Gaussian component of size broadening of the polar rhombohedral phase (R3m) and the Lorentzian component of strain broadening of the paraelectric cubic phase (Pm (3) over barm) are apposite for satisfactory Rietveld refinement of the synchrotron XRD data for all PMN samples. The volume-average crystallite size of PNRs (R3m phase) is almost invariant (approximately 12 nm) with increasing processing temperature while their weight percentage increases. The values of the apparent microstrain in the paraelectric cubic phase (Pm (3) over barm) are larger for hot-pressed samples.

引用

页码：1095 / 1104

页数：10

共 65 条

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