Evolution of the torsion-curvature of a crystal lattice upon the deformation of polycrystalline Cu–Al and Cu–Mn solid solutions: The role of grain size

The crystal structures of 10-methylacridinium chloride monohydrate, bromide monohydrate and iodide were determined by X-ray analysis. The compounds crystallize in the triclinic space group, P¯1, with 2 molecules in the unit cell. The molecular arrangement in the crystals revealed that hydrogen bonds (in hydrates) and van der Waals contacts play a significant part in intermolecular interactions. To discover their nature, contributions to the crystal lattice energy arising from electrostatic (the most important since the compounds form ionic crystals), dispersive and repulsive interactions were calculated. Enthalpies of formation of the salts, their stability and susceptibility to decomposition could be predicted from a combination of crystal lattice energies with values of other thermochemical characteristics obtained theoretically or taken from the literature. The role of water in the stabilization of the crystal lattice of the hydrates is also explained. The information gathered has given an insight into the features and behaviour of compounds which can be regarded as models of a large group of aromatic quaternary nitrogen salts.

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Magmatic Focusing to Mid-Ocean Ridges: The Role of Grain-Size Variability and Non-Newtonian Viscosity

Geochemistry Geophysics Geosystems ◽

10.1002/2017gc007048 ◽

2017 ◽

Vol 18 (12) ◽

pp. 4342-4355 ◽

Cited By ~ 8

Author(s):

Andrew J. Turner ◽

Richard F. Katz ◽

Mark D. Behn ◽

Tobias Keller

Keyword(s):

Grain Size ◽

Newtonian Viscosity ◽

Ocean Ridges ◽

Size Variability

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The Role of Microstructure on the Tensile Plastic Behaviour of Ductile Iron GJS 400 Produced through Different Cooling Rates—Part II: Tensile Modelling

Metals ◽

10.3390/met9091019 ◽

2019 ◽

Vol 9 (9) ◽

pp. 1019 ◽

Cited By ~ 5

Author(s):

Angella ◽

Donnini ◽

Ripamonti ◽

Górny ◽

Zanardi

Keyword(s):

Grain Size ◽

Ductile Iron ◽

Volume Fraction ◽

Interlamellar Spacing ◽

Flow Curves ◽

Cooling Rates ◽

Plastic Behaviour ◽

Microstructure Parameters ◽

Explicit Correlation

Tensile testing on ductile iron GJS 400 with different microstructures produced through four different cooling rates was performed in order to investigate the relevance of the microstructure’s parameters on its plastic behaviour. Tensile flow curve modelling was carried out with the Follansbee and Estrin-Kocks-Mecking approach that allowed for an explicit correlation between plastic behaviour and some microstructure parameters. In the model, the ferritic grain size and volume fraction of pearlite and ferrite gathered in the first part of this investigation were used as inputs, while other parameters, like nodule count and interlamellar spacing in pearlite, were neglected. The model matched very well with the experimental flow curves at high strains, while some mismatch was found only at small strains, which was ascribed to the decohesion between the graphite nodules and the ferritic matrix that occurred just after yielding. It can be concluded that the plastic behaviour of GJS 400 depends mainly on the ferritic grain size and pearlitic volume fraction, and other microstructure parameters can be neglected, primarily because of their high nodularity and few defects.

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