Microscopic Mechanism of Stripe Pairing Phase Formation

The subject of reactive phase formation in multilayer thin films of varying periodicity has stimulated much research over the past few years. Recent studies have sought to understand the reactions that occur during the annealing of Ni/Al multilayers. Dark field imaging from transmission electron microscopy (TEM) studies in conjunction with in situ x-ray diffraction measurements, and calorimetry experiments (isothermal and constant heating rate), have yielded new insights into the sequence of phases that occur during annealing and the evolution of their microstructure.In this paper we report on reactive phase formation in sputter-deposited lNi:3Al multilayer thin films with a periodicity A (the combined thickness of an aluminum and nickel layer) from 2.5 to 320 nm. A cross-sectional TEM micrograph of an as-deposited film with a periodicity of 10 nm is shown in figure 1. This image shows diffraction contrast from the Ni grains and occasionally from the Al grains in their respective layers.

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TEM investigations of surface residual stress relaxation in A12O3 and Al2O3-SiC nanocomposite

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170876 ◽

1994 ◽

Vol 52 ◽

pp. 628-629

Author(s):

J. Fang ◽

H. M. Chan ◽

M. P. Harmer

Keyword(s):

Residual Stress ◽

Single Phase ◽

Stress Relief ◽

Stress Recovery ◽

Surface Residual Stress ◽

Microscopic Mechanism ◽

Sic Particles ◽

Annealing Procedure ◽

The Difference ◽

Nano Size

It was Niihara et al. who first discovered that the fracture strength of Al2O3 can be increased by incorporating as little as 5 vol.% of nano-size SiC particles (>1000 MPa), and that the strength would be improved further by a simple annealing procedure (>1500 MPa). This discovery has stimulated intense interest on Al2O3/SiC nanocomposites. Recent indentation studies by Fang et al. have shown that residual stress relief was more difficult in the nanocomposite than in pure Al2O3. In the present work, TEM was employed to investigate the microscopic mechanism(s) for the difference in the residual stress recovery in these two materials.Bulk samples of hot-pressed single phase Al2O3, and Al2O3 containing 5 vol.% 0.15 μm SiC particles were simultaneously polished with 15 μm diamond compound. Each sample was cut into two pieces, one of which was subsequently annealed at 1300° for 2 hours in flowing argon. Disks of 3 mm in diameter were cut from bulk samples.

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In-situ investigation by X-ray diffraction and wafer curvature of phase formation and stress evolution during metal thin film – silicon reactions

Zeitschrift für Kristallographie Supplements ◽

10.1524/zksu.2007.2007.suppl_26.81 ◽

2007 ◽

Vol 2007 (suppl_26) ◽

pp. 81-89

Author(s):

O. Thomas

Keyword(s):

Thin Film ◽

Phase Formation ◽

Stress Evolution ◽

X Ray Diffraction ◽

X Ray ◽

Wafer Curvature ◽

Thin Film Silicon ◽

Metal Thin Film ◽

In Situ Investigation

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Features of phase formation at the interfaces of structural elements in multi-component ceramics based on Ti-Al-C

Functional materials ◽

10.15407/fm26.04.748 ◽

2019 ◽

Vol 26 (3) ◽

Keyword(s):

Phase Formation ◽

Structural Elements

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On the trustability of semi-empirical methods to the calculation of gas phase formation enthalpies of inorganic compounds containing heavy metals: tin borates

10.26434/chemrxiv.5393953.v1 ◽

2017 ◽

Author(s):

Robson de Farias

Keyword(s):

Heavy Metals ◽

Gas Phase ◽

Phase Formation ◽

Inorganic Compounds ◽

Formation Enthalpy ◽

Computational Time ◽

Gas Formation ◽

Formation Enthalpies ◽

Knudsen Effusion Mass Spectrometry ◽

Semi Empirical

In the present work, are calculated the gas formation enthalpies (SE; PM3 and PM6) for tin borates: SnB2O4 and Sn2B2O5. The calculated values are compared with experimental ones, obtained by Knudsen effusion mass spectrometry [3]. It is shown that SE methods, besides their lower computational time consuming can, indeed, provide reliable gas phase formation enthalpy values for inorganic compounds containing heavy metals.

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