Simultaneous X-ray diffraction and calorimetric study of metastable-to-stable solid phase transformation of 1,2-dipalmitoyl-sn-glycerol

With a high-temperature camera, designed for in situ synchrotron radiation X-ray topography, the crystallography of the α → β transition in titanium has been studied.

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Derived crystal structure of martensitic materials by solid–solid phase transformation

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273320006087 ◽

2020 ◽

Vol 76 (4) ◽

pp. 521-533 ◽

Cited By ~ 1

Author(s):

Mostafa Karami ◽

Nobumichi Tamura ◽

Yong Yang ◽

Xian Chen

Keyword(s):

Crystal Structure ◽

Phase Transformation ◽

Orientation Relationship ◽

Solid Phase ◽

Lattice Parameters ◽

Orthorhombic Symmetry ◽

Face Centered Cubic ◽

X Ray ◽

Solid Phase Transformation ◽

Martensitic Materials

A mathematical description of crystal structure is proposed consisting of two parts: the underlying translational periodicity and the distinct atomic positions up to the symmetry operations in the unit cell, consistent with the International Tables for Crystallography. By the Cauchy–Born hypothesis, such a description can be integrated with the theory of continuum mechanics to calculate a derived crystal structure produced by solid–solid phase transformation. In addition, the expressions for the orientation relationship between the parent lattice and the derived lattice are generalized. The derived structure rationalizes the lattice parameters and the general equivalent atomic positions that assist the indexing process of X-ray diffraction analysis for low-symmetry martensitic materials undergoing phase transformation. The analysis is demonstrated in a CuAlMn shape memory alloy. From its austenite phase (L21 face-centered cubic structure), it is identified that the derived martensitic structure has orthorhombic symmetry Pmmn with the derived lattice parameters a d = 4.36491, b d = 5.40865 and c d = 4.2402 Å, by which the complicated X-ray Laue diffraction pattern can be well indexed, and the orientation relationship can be verified.

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Wide angle X-ray diffraction study of the solid-phase chlorinated poly(ethylene)

Polymer ◽

10.1016/j.polymer.2004.06.017 ◽

2004 ◽

Vol 45 (18) ◽

pp. 6341-6348 ◽

Cited By ~ 6

Author(s):

S. Stoeva ◽

A. Popov ◽

R. Rodriguez

Keyword(s):

Diffraction Study ◽

Solid Phase ◽

Wide Angle ◽

X Ray Diffraction ◽

X Ray ◽

Poly Ethylene

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PREPARATION OF ANTIMONY-PLATINUM SURFACE ALLOY ELECTRODE BY ATOM DIFFUSION IN THE SOLID PHASE

International Journal of Modern Physics B ◽

10.1142/s0217979206040751 ◽

2006 ◽

Vol 20 (25n27) ◽

pp. 3999-4004

Author(s):

HIROSHI MATSUI ◽

KAZUFUMI WATANABE

Keyword(s):

Diffraction Pattern ◽

Low Temperatures ◽

Solid Phase ◽

Electrochemical Measurement ◽

X Ray Diffraction ◽

Platinum Surface ◽

X Ray ◽

Atom Diffusion ◽

Heat Treated ◽

Titanium Substrates

Antimony-platinum bilayers were prepared on titanium substrates by the two-step electrodeposition in the usual baths, and then surface alloys were formed by the atom diffusion in the solid phase. The simple antimony layer was little influenced by the substrate in both the measurements of X-ray diffraction and the i - E characteristic in a sulfuric acid solution. Regarding the bilayers, the catalytic activity in hydrogen evolution reaction was very sensitive to the presence of platinum, while the hydrogen adsorbability was quite insensitive. An interaction between antimony and platinum was confirmed by the appearance of a new dissolution wave in the electrochemical measurement and the occurrence of a new diffraction in the X-ray diffraction pattern after the heat-treatment of about 400°C. Although the new diffraction disagreed with any of the reported alloys, clear diffraction pattern of PtSb 2 alloy was observed, when the bilayers were heat-treated at about 600°C for one hour. Considering the penetration depth of X-ray, the alloying of antimony and platinum seems to occur also at low temperatures at least at the top surface.

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