scholarly journals Precipitation sequence of an aged Al-Mg-Si alloy

2010 ◽  
Vol 46 (2) ◽  
pp. 171-180 ◽  
Author(s):  
X. Fang ◽  
M. Song ◽  
K. Li ◽  
Y. Du
Keyword(s):  
Solid Solution ◽  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Supersaturated Solid Solution ◽  
Metastable Phase ◽  
Stable Phase ◽  
Precipitation Sequence ◽  
Maximum Hardness ◽  
Strengthening Phase ◽  
Transmission Electron

Heat treatable Al-Mg-Si alloys can be strengthened via the precipitation of metastable phase particles. The precipitation sequence of an Al-0.89Mg-0.75Si alloy with trace Fe and Zn elements during aging at 180 ?C has been investigated by transmission electron microscope (TEM), high resolution transmission electron microscope (HRTEM) and hardness measurements. It has been shown that the precipitation sequence of the alloy can be identified as follows: supersaturated solid solution ? G.P. zones ? metastable ?? precipitates ? metastable ?? precipitates ? stable ? phase + Si particles. It is indicated that ?? phase remains stable up to 30 hours at 180?C. The hardness measurements during aging realize that the main strengthening phase for the investigated Al-Mg-Si alloy is ?? precipitates and the maximum hardness is obtained after aging at 180 ?C for 4~6.5 hours.

Metastable Phase Formation in the Ti-rich end of the Ti-(Co,Ni) System

1989 ◽  
Vol 157 ◽  
Author(s):  
David A Lilienfeld ◽  
Peter Bergesen
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Composition Range ◽  
Metastable Phase ◽  
Ternary Alloys ◽  
Stable Phase ◽  
Transmission Electron ◽  
Metastable Phase Formation ◽  
Nitrogen Ion ◽  
Fcc Phase

ABSTRACTThe Ti-rich end of the Ti-(Co,Ni) was investigated by ion mixing. A metastable FCC phase was discovered which formed over a broad composition range. The stable phase was formed by ion mixing at 350°C in some samples but was not formed until 550°C during in situ heating in the Transmission electron microscope. Some of the Ni-rich ternary alloys did not amorphize even after liquid nitrogen ion irradiations. This result indicates that the amorphization mechanism for the TiNi CsCl phase is different from that of the TiCo CsCl phase.

Transmission Electron Microscope Study of Interfacial Reactions in Gold-Germanium Contact to Gallium Arsenide

1985 ◽  
Vol 54 ◽  
Author(s):  
Taeil Kim ◽  
D.D.L. Chung
Keyword(s):  
Electron Microscopy ◽  
Solid Solution ◽  
Transmission Electron Microscopy ◽  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Electron Microscope Study ◽  
Lattice Match ◽  
Perfect Lattice ◽  
Transmission Electron ◽  
Transmission Electron Microscope Study

ABSTRACTThe structure of 500 Å Au/500 A Ge/500 Å Au/GaAs (100) was studied by transmission electron microscopy after annealing at 350 – 500°C. Annealing at 350 – 450°C caused the formation of AuGeAs with a (110) texture, but this phase disappeared after annealing at 500°C. The hexagonal a-AuGa (or AuGa) was formed after annealing at 400°C, such that (111)Au // (0001)a, and [110]AU // [1120]a and there was perfect lattice match between Au (i.e., Au-rich solid solution) and a-AuGa. After annealing at 450°C or above, a phase tentatively identified as the hexagonal Au3Ga was formed and Ge (i.e., Ge-rich solid solution) became epitaxial to (100) GaAs. Annealing at 400°C caused Au to change from no texture to a (110) texture.

Study of Au Precipitation from Solid Solution in Si

1974 ◽  
Vol 32 ◽  
pp. 496-497
Author(s):  
A. G. Cullis
Keyword(s):  
Solid Solution ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Transmission Electron Microscope ◽  
Transmission Electron ◽  
Scanning Electron

In a previous study of impurity gettering in Si it was found that Au-containing precipitates were formed at the surfaces of wafers which had been equilibrated with Au at 1200°C and then subjected to B diffusion at 1000°C. The work reported in summary here relates to the characterization of the precipitates and to the construction of a model for their growth. This investigation involved the use of both the transmission electron microscope (TEM) and the scanning electron microscope (SEM). Full details will be reported elsewhere.

Observation of large Equilibrium Phase of Al-Mg-Si Alloys

2014 ◽  
Vol 794-796 ◽  
pp. 977-980
Author(s):  
Shintaro Hida ◽  
Šárka Mikmeková ◽  
Kenji Matsuda ◽  
Susumu Ikeno
Keyword(s):  
Solid Solution ◽  
Orientation Relationship ◽  
Supersaturated Solid Solution ◽  
Metastable Phase ◽  
Equilibrium Phase ◽  
Precipitation Sequence ◽  
Hexagonal Plate ◽  
Β Phase ◽  
Hexagonal Shape ◽  
Al Matrix

The precipitation sequence in Al-Mg-Si alloy is generally accepted as supersaturated solid solution GP-zone β β β (Mg2Si). The effect of Ag or Cu in Al-Mg-Si alloy was reported in our previous work. There is little report about effect of Ag or Cu on the metastable phase and equilibrium phase in this alloy the system. Hexagonal plate like β-phase and Q-phase were observed the Cu added alloy. This hexagonal-shaped β-phase has unique orientation relationship to the Al matrix. This work was performed to compare the shape of effect of the additional elements on the equilibrium phase. The hexagonal shape precipitate was observed in Cu or Ag added alloys aged at 673K.

scholarly journals Controlling the optical and structural properties of ZnS–AgInS2 nanocrystals by using a photo-induced process

2014 ◽  
Vol 5 ◽  
pp. 1767-1773 ◽  
Author(s):  
Takashi Yatsui ◽  
Fumihiro Morigaki ◽  
Tadashi Kawazoe
Keyword(s):  
Solid Solution ◽  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Visible Region ◽  
Size Variation ◽  
Excitation Wavelength ◽  
Nanophotonic Devices ◽  
Transmission Electron ◽  
Microscope Images ◽  
Low Toxicity

ZnS–AgInS2 (ZAIS) solid-solution nanocrystals are promising materials for nanophotonic devices in the visible region because of their low toxicity and good emission properties. We developed a technique of photo-induced synthesis to control the size and composition of the ZAIS nanocrystals. This method successfully decreased the defect levels, as well as the size and size variation of ZAIS nanocrystals by controlling the excitation wavelength during synthesis. Detailed analysis of transmission electron microscope images confirmed that the photo-induced synthesis yielded a high crystallinity of the ZAIS nanocrystals with small variations in size and content.

HRTEM Observation of the Age Hardening Precipitates in Mg-Gd-Sc Alloys, with Different Gd Concentrations

2011 ◽  
Vol 409 ◽  
pp. 335-338
Author(s):  
Takafumi Fujii ◽  
Kenji Matsuda ◽  
Tokimasa Kawabata ◽  
Susumu Ikeno
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Transmission Electron Microscope ◽  
Age Hardening ◽  
Number Density ◽  
Maximum Hardness ◽  
Β Phase ◽  
Transmission Electron ◽  
Hrtem Observation

High resolution transmission electron microscope (HRTEM) observations were performed to investigate the age hardening precipitates in Mg-Gd-Sc alloys. The maximum hardness of these alloys increased with Gd content. The precipitates with the features of β” phase and β’ phase in Mg-Gd alloy were observed in Mg-15Gd-6.4Sc and Mg-10Gd-6.4Sc alloys. Maximum hardness and number density of precipitate in Mg-15Gd-6.4Sc alloy were higher than that in Mg-10Gd-6.4Sc alloy, and the finer precipitates with higher number of density were contributed to the maximum hardness in Mg-Gd-Sc alloys.

A Reproducible Selective Stain for Cardiac Sarcoplasmic Reticulum

1974 ◽  
Vol 32 ◽  
pp. 214-215
Author(s):  
R. A. Waugh ◽  
J. R. Sommer
Keyword(s):  
Complex System ◽  
Electron Microscope ◽  
Sarcoplasmic Reticulum ◽  
Transmission Electron Microscope ◽  
Electron Microscopic ◽  
Cardiac Sarcoplasmic Reticulum ◽  
Transmission Electron

Cardiac sarcoplasmic reticulum (SR) is a complex system of intracellular tubules that, due to their small size and juxtaposition to such electron-dense structures as mitochondria and myofibrils, are often inconspicuous in conventionally prepared electron microscopic material. This study reports a method with which the SR is selectively “stained” which facilitates visualizationwith the transmission electron microscope.

Surface Structure of the Spores of Glugea Weissenbergi

1969 ◽  
Vol 27 ◽  
pp. 238-239
Author(s):  
Sanford H. Vernick ◽  
Anastasios Tousimis ◽  
Victor Sprague
Keyword(s):  
Electron Microscope ◽  
Surface Structure ◽  
Transmission Electron Microscope ◽  
Mature Spore ◽  
Spore Surface ◽  
Sectioned Material ◽  
Transmission Electron ◽  
Surface Detail

Recent electron microscope studies have greatly expanded our knowledge of the structure of the Microsporida, particularly of the developing and mature spore. Since these studies involved mainly sectioned material, they have revealed much internal detail of the spores but relatively little surface detail. This report concerns observations on the spore surface by means of the transmission electron microscope.

A New High Resolution Transmission Electron Microscope with Second-Zone Objective Lens

1969 ◽  
Vol 27 ◽  
pp. 176-177 ◽  
Author(s):  
H. Tochigi ◽  
H. Uchida ◽  
S. Shirai ◽  
K. Akashi ◽  
D. J. Evins ◽  
...  
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Transmission Electron Microscope ◽  
Objective Lens ◽  
High Excitation ◽  
Transmission Electron ◽  
New Instrument

A New High Excitation Objective Lens (Second-Zone Objective Lens) was discussed at Twenty-Sixth Annual EMSA Meeting. A new commercially available Transmission Electron Microscope incorporating this new lens has been completed.Major advantages of the new instrument allow an extremely small beam to be produced on the specimen plane which minimizes specimen beam damages, reduces contamination and drift.

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