Effect of Nickel and Aluminium on Solid State Transformations in SG Iron

1984 ◽  
Vol 34 ◽  
Author(s):  
A. C. Ganguli ◽  
A. K. Chakrabarti ◽  
S. C. Dasgupta
Keyword(s):  
Solid State ◽  
Solution Treatment ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
X Ray ◽  
Temperature Range ◽  
Microscopic Studies ◽  
Sg Iron ◽  
The Individual ◽  
Kinetics Of

ABSTRACTThe individual and combined addition of nickel and aluminium to S.g. iron influences several solid state transformations. Nickel depresses the temperature range for reversion of ferrite and pearlite to austenite on heating, while aluminium raises it. Combined addition of nickel and aluminium restores the temperature range closer to that for unalloyed iron. But nickel enhances the kinetics of ferritisation during tempering and weakly retards recrystallisation of ferrite grains. Aluminium strongly retards both the ferritisation and recrystallisation processes. Ferritisation kinetics is enhanced and recrystallisation of ferrite grains is also hastened in alloys containing nickel and aluminium. Alloys containing nickel and aluminium also respond to agehardening treatment in the temperature range 450–550°C after a solution treatment-cum-ferritising anneal at 700°C. On the basis of X-ray diffraction and electron microscopic studies, a probable mechanism of ageing has been proposed.

Synthesis of nanometer-sized particles of barium orthotitanate prepared through a modified reverse micellar route: Structural characterization, phase stability and dielectric properties

2004 ◽  
Vol 19 (10) ◽  
pp. 2905-2912 ◽  
Author(s):  
Tokeer Ahmad ◽  
Ashok K. Ganguli
Keyword(s):  
Martensitic Transition ◽  
Line Broadening ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
X Ray ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
Microscopic Studies ◽  
Size Of Particles ◽  
Reverse Micellar

Nanoparticles of barium orthotitanate (Ba2TiO4) was obtained using microemulsions (avoiding Ba-alkoxide). Powder x-ray diffraction studies of the powder after calcining at 800 °C resulted in a mixture of orthorhombic (70%) and monoclinic (30%) phases. The high-temperature orthorhombic form present at 800 °C was due to the small size of particles obtained by the reverse micellar route. Pure orthorhombic Ba2TiO4 was obtained on further sintering at 1000 °C with lattice parameters a = 6.101(2) Å, b =22.94(1) Å, c = 10.533(2) Å (space group, P21nb). The particle size obtained from x-ray line broadening studies and transmission electron microscopic studies was found to be 40–50 nm for the powder obtained after heating at 800 °C. Sintering at 1000 °C showed increase in grain size up to 150 nm. Our studies corroborate well with the presence of a martensitic transition in Ba2TiO4. The dielectric constant was found to be 40 for Ba2TiO4 (at 100 kHz) for samples sintered at 1000 °C. The dielectric loss obtained was low (0.06) at 100 kHz.

scholarly journals ELECTRON MICROSCOPE STUDIES ON THE HAEMOGLOBIN MOLECULES

1961 ◽  
Vol 10 (1) ◽  
pp. 113-120 ◽  
Author(s):  
S. N. Chatterjee ◽  
P. Sadhukhan ◽  
J. B. Chatterjea
Keyword(s):  
Electron Microscope ◽  
Satisfactory Agreement ◽  
Human Subjects ◽  
Average Height ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
X Ray ◽  
Diffraction Model ◽  
Normal Human ◽  
The Individual

Haemoglobin molecules isolated from normal human subjects have been directly micrographed under the electron microscope following in general Hall's technique. The average height (h) and the widths along (w11) and perpendicular (w⊥) to the shadow direction of the molecules have been measured as 56.5 ± 6.6 A, 122.7 ± 15 A, and 120.9 ± 20 A, respectively. The exaggeration in the molecular widths due to the deposition of metal cap ranges between 60 to 70 A. The probable resolution of the substructure of the molecule, e.g., presence of "holes" and dimples, in the present electron microscopic evidence has been discussed. The electron microscopic results on the size of the individual haemoglobin molecules are in satisfactory agreement with the recent x-ray diffraction model of Perutz and his associates for horse haemoglobin.

Fabrication of SnS2 Flower Like Nanoflake Assemblies Through Thermal Evaporation

2007 ◽  
Vol 7 (12) ◽  
pp. 4540-4545 ◽  
Author(s):  
Subhajit Biswas ◽  
Soumitra Kar ◽  
Tandra Ghoshal ◽  
Subhadra Chaudhuri
Keyword(s):  
Thermal Evaporation ◽  
Growth Direction ◽  
Vapor Concentration ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
X Ray ◽  
Raman Spectroscopic ◽  
Transmission Electron ◽  
Scanning Electron Microscopic ◽  
The Individual

Uniform as well as flower like patterns of SnS2 nanoflakes were produced by a thermal evaporation process. Interpenetrating phenomenon was observed between the individual nanoflakes during the course of their lateral growth. The interpenetrating growth and controlled vapor concentration as well as the substrate temperature leads to the formation of flower like assemblies of SnS2 nanoflakes. Morphology and growth mechanism of the nanostructures were studied by scanning electron microscopic observations at different stages of the nanoflake growth. The produced nanoflakes were characterized by X-ray diffraction, scanning and transmission electron microscopy, and Raman spectroscopic measurements. SnS2 nanoflakes were perfectly single crystalline and growth direction of the nanoflakes was along the {101}-lattice plane.

scholarly journals Electron Microscopic Studies of Ilmenite from the Chhatrapur Coast, Odisha, India, and Their Implications in Processing

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
D. S. Rao ◽  
D. Sengupta
Keyword(s):  
Optical Microscope ◽  
Particle Size Analysis ◽  
Eastern Ghats ◽  
Metamorphic Rocks ◽  
Size Analysis ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
X Ray ◽  
Weathering Processes ◽  
Microscopic Studies

Ilmenite from the Chhatrapur coast, Odisha, India, was studied using optical microscope, X-ray diffraction, particle size analysis, and electron microprobe to decipher their micromorphology, texture(s), and elemental composition. The micromorphological features by electron microscope indicate that weathering processes such as mechanical and chemical, affected the placer heavy mineral ilmenite. These detrital ilmenites contain TiO2 in the range of 50.25% to 55.41% and FeO 42.72% to 49.99% in addition to Al2O3, MgO, MnO, CaO, Na2O, Cr2O3, NiO, ZnO, ZrO2, V2O5, and HfO2 (0 to 0.034%). Ti/(Ti + Fe) ratio in the ilmenite varied from 0.413 to 0.5, which indicates the effect of weathering/oxidation confirming microscopic observations. All the results revealed that these ilmenite grains were derived from the gneissic/granitic, basic and high grade metamorphic rocks, belonging to the Eastern Ghats Group of the Precambrian complex of coastal Orissa.

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