Thermal Analysis of Solidifying Secondary Phases in the Eutectic Al-Si Alloy and the Effect of Sr and Fe

2014 ◽  
pp. 285-292
Author(s):  
Jeyakumar Manickaraj ◽  
Anton Gorny ◽  
Sumanth Shankar
Keyword(s):  
Thermal Analysis ◽  
Secondary Phases

scholarly journals Processing of Bi–Sr–Ca–Cu–O glasses using platinum and alumina crucibles

1992 ◽  
Vol 7 (8) ◽  
pp. 2035-2039 ◽  
Author(s):  
T.G. Holesinger ◽  
D.J. Miller ◽  
S. Fleshler ◽  
L.S. Chumbley
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Grain Boundaries ◽  
Annealed Sample ◽  
Substrate Material ◽  
Superconducting Phase ◽  
Transition Temperatures ◽  
Secondary Phases ◽  
Second Phases ◽  
Potential Substrate

Reactions with alumina and platinum crucibles were studied during the preparation of Bi2Sr2Ca1Cu2Oy “2212” glasses. In particular, reactions with Al2O3 are of interest since alumina is a potential substrate material in applications of this superconductor. Glasses processed using alumina crucibles were completely homogeneous and free of secondary phases although the material contained 2.26 at. % Al in solution. After heat treatments, Al was found in the form of SrCaAlOy particles located primarily along grain boundaries of the 2212 superconducting phase. Platinum contamination was minimal (<0.02 at. %) and no Pt-containing secondary phases were found in amorphous or annealed samples. Glasses made with Pt crucibles were found to contain small amounts of CaO, Sr14−xCaxCu24O41, and 2201 as second phases. Differential thermal analysis (DTA) suggested that the crystallization processes were essentially the same for all samples although the small amount of Al seemed to slow the kinetics leading to the formation of 2212. Neither Al nor Pt was detected within the 2212 phase. The measured superconducting compositions in each annealed sample were nearly the same with identical transition temperatures of 88 K. Overall differences in stoichiometry were accommodated by changes in the number and composition of the secondary phases present.

scholarly journals Characterization and kinetic modeling of secondary phases in squeeze cast Al alloy A380 by DSC thermal analysis

China Foundry ◽  
2017 ◽  
Vol 14 (2) ◽  
pp. 98-107 ◽  
Author(s):  
Xin-ping Hu ◽  
Li Fang ◽  
Jun-xiang Zhou ◽  
Xue-zhi Zhang ◽  
Henry Hu
Keyword(s):  
Thermal Analysis ◽  
Kinetic Modeling ◽  
Al Alloy ◽  
Secondary Phases ◽  
Squeeze Cast

Pb(Zr0.95Ti0.05)O3 Powders Synthesized by PEG Modified Pechini Method: Characterization and Sintering Behavior

2007 ◽  
Vol 26-28 ◽  
pp. 1105-1108
Author(s):  
Shao Jun Qiu ◽  
Hui Qing Fan ◽  
Xiao Dong Zheng ◽  
Jin Chen ◽  
Chen Yang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Aqueous Solution ◽  
Lead Zirconate Titanate ◽  
Pechini Method ◽  
Lead Zirconate ◽  
Sintering Behavior ◽  
Secondary Phases ◽  
Modified Pechini Method ◽  
Scanning Electron

To adjust the morphology and crystallinity of the chemically prepared Zr-riched` lead zirconate titanate (Pb(Zr0.95Ti0.05)O3) powders, polyethylene glycol (PEG 20000) was used in aqueous solution (modified Pechini method). Thermal analysis of the as-synthesized gel showed two distinct stages, which indicates the volatilization of water and the decomposition of polymers, respectively. When the gel were calcined at 400 oC, the powders consisted mainly of perovskite PZT accompanied with small amounts of secondary phases. The higher the calcination temperature applied, the stronger the intensity of XRD, which means the crystallinity were improved. Scanning electron microscopy of as-prepared powders suggested that the powders were soft agglomerate particles when calcined at 600 to 800 oC. Compared with the normal Pechini method, PEG could help the formation of crystalline phase and soft agglomerate. When the powders compacts were sintered at 975 to 1125 oC, high pure (>99.5%) of tetragonal phase ceramics were got having relative density of 85% to 94%.

Study on the Formation Mechanism and Sinterability of La1-x SrxCoO3-d (x = 0.1 - 0.3) Prepared by Mechanical Activation

2017 ◽  
Vol 68 (9) ◽  
pp. 2043-2047
Author(s):  
Georgeta Velciu ◽  
Adelina Carmen Ianculescu ◽  
Alina Melinescu ◽  
Virgil Marinescu ◽  
Maria Preda
Keyword(s):  
Thermal Analysis ◽  
Mechanical Activation ◽  
Formation Mechanism ◽  
Apparent Density ◽  
Raw Materials ◽  
Secondary Phases ◽  
Sem Images ◽  
Edx Analyses ◽  
Thermally Treated

In this work it was studying evolution of the reactions that occur at the formation of La1-xSrxCoO3-� from mixtures of La2O3, Co3O4 and SrCoO3, prepared by mechanical activation. It was found that distributions of the particles sizes after mechanical activation are unimodal and narrow. Thermal analysis shows that the reactions that occur under the temperature of 1000oC are dissociation reactions of the raw materials or of intermediate compounds formed in the process of mechanical activation. The first compound found, starting from 1000oC was LaCoO3, whereas Co3O4 and CoO were observed as secondary phases. By measuring the apparent density of the thermally treated samples, a good tendency to sintering was noticed. SEM images and EDX analyses allowed to highlight the high sinterability of the samples.

Structure, Thermal and Conductivity Behavior of Vanadium Substituted Li1.4Ti1.6Al0.4 (PO4)2.9(VO4)0.1 NASICON-Type

2019 ◽  
Vol 290 ◽  
pp. 60-64
Author(s):  
Tasiu Zangina ◽  
Jumiah Hassan ◽  
Raba’ah Syahidah Azis ◽  
Khamirul Amin Matori ◽  
Chifu Ebenezar Ndikilar ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Solid State ◽  
Lithium Aluminum ◽  
Secondary Phases ◽  
Solid State Method ◽  
X Ray ◽  
Nasicon Type ◽  
Vanadium Substitution ◽  
State Method ◽  
Conductivity Behavior

The material with NASICON-type structure, lithium aluminum titanium phosphate with vanadium substituting phosphorous (Li1.4Ti1.6Al0.4(PO4)2.9(VO4)0.1) (LATPV) has been synthesized via solid state method. The X-ray powder diffraction analysis shows the effect of vanadium in the composition LATPV. Various secondary phases have been observed due to vanadium substitution which leads to low ionic conductivity of σ = 2.5 x 10-5 (Ωm)-1. The thermal analysis indicated that the reaction of chemical mixture become stable at round 460 °C which indicated an improvement in the material densification.

Electron Energy Analysis of Germanium and Silica Layers on Silicon Substrates

1975 ◽  
Vol 33 ◽  
pp. 96-97
Author(s):  
R. W. Ditchfield ◽  
A. G. Cullis
Keyword(s):  
Epitaxial Growth ◽  
Electron Energy ◽  
Silicon Substrates ◽  
Secondary Phases ◽  
Si Substrates ◽  
Transmission Electron ◽  
Layer Structures ◽  
Si Films ◽  
Electron Energy Loss ◽  
Growth Centres

An energy analyzing transmission electron microscope of the Möllenstedt type was used to measure the electron energy loss spectra given by various layer structures to a spatial resolution of 100Å. The technique is an important, method of microanalysis and has been used to identify secondary phases in alloys and impurity particles incorporated into epitaxial Si films.Layers Formed by the Epitaxial Growth of Ge on Si Substrates Following studies of the epitaxial growth of Ge on (111) Si substrates by vacuum evaporation, it was important to investigate the possible mixing of these two elements in the grown layers. These layers consisted of separate growth centres which were often triangular and oriented in the same sense, as shown in Fig. 1.

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