Microstructural Characterization of the Crystallization Sequence of a Severe Plastically Deformed Al-Ce-Ni-Co Amorphous Alloy

2006 ◽  
Vol 519-521 ◽  
pp. 1329-1334 ◽  
Author(s):  
Zsolt Kovács ◽  
P. Henits ◽  
Alexandre P. Zhilyaev ◽  
Nguyen Q. Chinh ◽  
Ádám Révész

Discs of Al85Ce8Ni5Co2 amorphous alloy were severely deformed by high pressure torsion. Severe plastic deformation exceeding equivalent strain of 8.2 induces the formation of nanocrystalline fcc-Al in a more stable residual amorphous matrix. Calorimetric and X-ray diffraction measurements revealed that the deformed outer part of the disc crystallizes into a mixture of equilibrium phases during the first thermal event. However, in the amorphous ribbon the same crystalline mixture develops only after the second stage.

2014 ◽  
Vol 805 ◽  
pp. 343-349
Author(s):  
Carine F. Machado ◽  
Weber G. Moravia

This work evaluated the influence of additions of the ceramic shell residue (CSR), from the industries of Lost Wax Casting, in the modulus of elasticity and porosity of concrete. The CSR was ground and underwent a physical, chemical, and microstructural characterization. It was also analyzed, the environmental risk of the residue. In the physical characterization of the residue were analyzed, the surface area, and particle size distribution. In chemical characterization, the material powder was subjected to testing of X-ray fluorescence (XRF). Microstructural characterization was performed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The residue was utilized like addition by substitution of cement in concrete in the percentages of 10% and 15% by weight of Portland cement. It was evaluated properties of concrete in the fresh and hardened state, such as compressive strength, modulus of elasticity, absorption of water by total immersion and by capillarity. The results showed that the residue can be used in cement matrix and improve some properties of concrete. Thus, the CSR may contribute to improved sustainability and benefit the construction industry.


1996 ◽  
Vol 433 ◽  
Author(s):  
Jeong Soo Lee ◽  
Hyun JA Kwon ◽  
Young Woo Jeong ◽  
Hyun HA Kim ◽  
Kyu HO Park ◽  
...  

AbstractMicrostructures and interdiffusions of Pt/Ti/SiO2/Si and RuO2/SiO2/Si during annealing in O2 were investigated using x-ray diffraction, Auger electron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The degree of oxidation and the interdiffusion of elements have remarkably increased with increasing temperature above 500 °C for the Pt/Ti/SiO2/Si case. The generation of Pt hillocks commenced at 500 °C. The Pt-silicide phase was also observed near the TiOx/SiO2 interface. The microstructural variations occurred to only a small amount for the RuO2/SiO2/Si case over the temperature range 300 – 700 °C. While there was no hillock formation, the RuO2 film surface was roughened by the thermal grooving phenomenon. A thin interlayer phase was found at the RuO2/SiO2 interface.


RSC Advances ◽  
2016 ◽  
Vol 6 (53) ◽  
pp. 47373-47381 ◽  
Author(s):  
Maxime Bodennec ◽  
Qing Guo ◽  
Dérick Rousseau

Lecithin-based oleogels consist of a worm-like entangled fibrous 3D network. Small angle X-ray diffraction suggests that these microfibres are formed by the packing of reverse hexagonal (HII) tubules parallel to the axis of fibres.


2012 ◽  
Vol 616-618 ◽  
pp. 1732-1735 ◽  
Author(s):  
Xi Hai Shen ◽  
Yu Gang Zheng ◽  
Liang Chang ◽  
Jin Jia Guo ◽  
Song Bin Ye ◽  
...  

Aiming at the glass-to-metal seals serving in the Solar Thermal Power (STP), glass-to-metal vacuum brazed joints were studied. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis were performed to examine the microstructure and element contents of interface seam on the glass-to-metal vacuum brazed joints. Also, the compositional concentration of the interface seam was measured by using energy dispersive spectroscopy (EDS).


2016 ◽  
Vol 869 ◽  
pp. 159-163
Author(s):  
Danúbia Lisbôa da Costa ◽  
Ingrid Mayara Medeiros Fernandes ◽  
Aluska Nascimento Simões Braga ◽  
Rosiane Maria da Costa Farias ◽  
Romualdo Rodrigues Menezes ◽  
...  

Ornamental rocks are among the most promising business areas of the mineral sector, raising the necessity for, besides beauty, investments in quality, safety and characterization in the various application fields of these rocks. So, this work aims at the microstructural characterization of the class of these rocks: the Cariri Rocks, also known the limestone, which are calcareous rocks mainly formed by calcium and magnesium carbonate, possibly presenting variations due to their origins. For characterization, we studied four samples, being two from Chapada do Apodi and two from Chapada do Araripe, characterized physically and micro-structurally through chemical analysis, X-ray diffraction, optical micrography and porosimetry tests. The results prove that the limestones are calcitic and dolomitic, and present porosity varying from 5 to 15%, with pores concentration between 100nm and 10μm, besides the high microstructural heterogeneity.


1989 ◽  
Vol 168 ◽  
Author(s):  
R. A. Lowden ◽  
K. L. More ◽  
T. M. Besmann ◽  
R. D. James

AbstractChemical vapor deposition has been utilized to produce ternary, multiphase coatings of various compositions of silicon carbide (SiC) with Ti, Cr, and Mo. Thermodynamic calculations have been performed for a variety of experimental conditions in each system. Scanning, transmission and analytical electron microscopy, and X-ray diffraction techniques have been used to characterize the microstructures and to determine compositions.


1998 ◽  
Vol 13 (9) ◽  
pp. 2580-2587 ◽  
Author(s):  
K. H. Ryu ◽  
J-M. Yang

The characteristics of nanosized silicon nitride powders with doped Y2O3 and Al2O3 fabricated by a plasma-reacted chemical process were investigated. The chemical compositions of the powders were analyzed by wet chemical analysis. The morphology and the size distribution were determined by transmission electron microscopy (TEM). TEM with energy dispersive spectroscopy (EDS) was used to verify the existence of sintering additives in each individual particle. The crystal structure of the powders was identified by the selected area diffraction pattern (SADP). X-ray diffraction (XRD) technique was used for phase analysis and the measurement of degree of crystallinity. The characteristics of chemical bonding was analyzed by using Fourier transform infrared spectroscopy (FTIR).


1987 ◽  
Vol 99 ◽  
Author(s):  
G. J. Fisanick ◽  
P. Mankeewicht ◽  
W. Skocpolt ◽  
R. E. Howardt ◽  
A. Dayem ◽  
...  

ABSTRACTBa2YCu3O7 films produced by co-evaporation of BaF2, Cu and Y onto <100> S1TiO3 substrates in an O2 ambient followed by post-annealing were analyzed using RBS, X-ray diffraction and Auger microscopy. These films exhibit Tc's (R=0) of =90K and a best Jc of > 1.0×106 A/cm2 at 81K for a =2500A thick film. RBS and Auger depth profiling limit the level of F present in the post-annealed films to <5 at. %, although F is evident in the as-deposited material. RBS channeling experiments yield a Xmin=31%, demonstrating the epitaxial quality of the films. X-ray diffraction shows that the films are predominantly oriented with c-axis perpendicular to the substrate, with narrow mosaic spread in-plane. A small portion of the film is in the form of needles oriented with a-axis perpendicular to the substrate, whose areal density is dependent on annealing conditions and local film stoichiometry. Scanning Auger microscopy confirms that the needles and c-axis plateaus have the same metal and oxygen stoichiometry. Also present in the film are insulating balls which appear to nucleate terraces in the c-axis perpendicular structure. Scanning Auger shows that these features are also close to the metals stoichiometry, but are C rich compared to the needles. The plateaus are covered with =11 times more C than the needles, indicating that the basal plane surface is highly reactive. Auger depth profiling and RBS show little evidence for interdiffusion.


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