Influence of Inter-Lamellar Spacing of Pearlite Phase on Spheroidized Annealed Structure

2020 ◽  
pp. 343-358
Author(s):  
Partha Sarathi Sarkar ◽  
Bhavesh Rameshchandra Rana ◽  
Pinkal D. Mistry
Keyword(s):  
Lamellar Spacing

Influence of convection on lamellar spacing of eutectics

1984 ◽  
Vol 67 (2) ◽  
pp. 343-352 ◽  
Author(s):  
V. Baskaran ◽  
William R. Wilcox
Keyword(s):  
Lamellar Spacing

Effect of Lamellar Spacing on Creep Strength of Ti-42mol%Al Alloy with Fully Lamellar Structure

1999 ◽  
Vol 171-174 ◽  
pp. 717-724
Author(s):  
Ryoichi Yamamoto ◽  
K. Mizoguchi ◽  
Kouichi Maruyama
Keyword(s):  
Creep Strength ◽  
Lamellar Structure ◽  
Lamellar Spacing ◽  
Al Alloy ◽  
Fully Lamellar

scholarly journals Versatile Controls of Microdomain Morphologies and Temperature Dependencies in Lamellar Spacing by Blending Diblock Copolymers Bearing Antisymmetric Compositions

ACS Omega ◽  
2017 ◽  
Vol 2 (12) ◽  
pp. 8580-8590 ◽  
Author(s):  
Junji Fukuhara ◽  
Akifumi Yasui ◽  
Katsuhiro Yamamoto ◽  
Shinichi Sakurai
Keyword(s):  
Diblock Copolymers ◽  
Lamellar Spacing

Creep Behavior and Microstructural Stability of Lamellar γ-T1AI (Cr, Mo, Si, B) with Extremely Fine Lamellar Spacing

2000 ◽  
Vol 646 ◽  
Author(s):  
Wolfram Schillinger ◽  
Dezhi Zhang ◽  
Gerhard Dehm ◽  
Arno Bartels ◽  
Helmut Clemens
Keyword(s):  
Creep Rate ◽  
Creep Behavior ◽  
Lamellar Microstructure ◽  
Lamellar Spacing ◽  
Primary Creep ◽  
Vacuum Arc ◽  
Internal Stresses ◽  
Microstructural Stability ◽  
Thermodynamical Equilibrium ◽  
Creep Tests

ABSTRACTγ-T1AI (Cr, Mo, Si, B) specimens with two different fine lamellar microstructures were produced by vacuum arc melting followed by a two-stage heat treatment. The average lamellar spacing was determined to be 200 nm and 25–50 nm, respectively. Creep tests at 700°C showed a very strong primary creep for both samples. After annealing for 24 hours at 1000 °C the primary creep for both materials is significantly decreased. The steady-state creep for the specimens with the wider lamellar spacing appears to be similar to the creep behavior prior to annealing while the creep rate of the material with the previously smaller lamellar spacing is significantly higher. Optical microscopy and TEM-studies show that the microstructure of the specimens with the wider lamellar specing is nearly unchanged, whereas the previously finer material was completely recrystallized to a globular microstructure with a low creep resistance. The dissolution of the fine lamellar microstructure was also observed during creep tests at 800 °C as manifested in an acceleration of the creep rate. It is concluded that extremely fine lamellar microstructures come along with a very high dislocation density and internal stresses which causes the observed high primary creep. The microstructure has a composition far away from the thermodynamical equilibrium which leads to a dissolution of the structure even at relatively low temperatures close to the intended operating temperature of γ-T1AI structural parts. As a consequence this limits the benefit of fine lamellar microstructures on the creep behavior.

Factors affecting the lamellar spacing in two-phase TiAl alloys with fully lamellar microstructures

2001 ◽  
Vol 36 (9) ◽  
pp. 1737-1742 ◽  
Author(s):  
Jiancheng Tang ◽  
Baiyun Huang ◽  
Kechao Zhou ◽  
Wensheng Liu ◽  
Yuehui He ◽  
...  
Keyword(s):  
Lamellar Spacing ◽  
Two Phase ◽  
Tial Alloys ◽  
Factors Affecting ◽  
Fully Lamellar

Atomic Force Microscopy of Annealed Plain Carbon Steels

2015 ◽  
Author(s):  
Surendra Kumar Gupta ◽  
Patricia Iglesias Victoria
Keyword(s):  
Atomic Force Microscopy ◽  
Optical Microscopy ◽  
Interlamellar Spacing ◽  
Lamellar Spacing ◽  
Optical Microscope ◽  
Carbon Steels ◽  
Force Microscopy ◽  
Atomic Force

Microstructure of annealed plain carbon steels is examined using optical microscopy. When the inter-lamellar spacing in pearlite is small, optical microscope at 1000X is unable to resolve the ferrite and cementite lamellae. In hyper-eutectoid steels, cementite in pearlite appears as darker phase whereas the pro-eutectoid cementite appears as a lighter phase. Atomic force microscopy (AFM) of etched steels is able to resolve ferrite and cementite lamellae in pearlite at similar magnifications. Both cementite in pearlite as well as pro-eutectoid cementite appear as raised areas (hills) in AFM images. Interlamellar spacing in pearlite increases with increasing hardenability of steel.

scholarly journals Lamellar spacing of photosystem II membrane fragments upon dehydration studied by neutron membrane diffraction

2015 ◽  
Vol 2 (1) ◽  
Author(s):  
Jörg Pieper ◽  
Leonid Rusevich ◽  
Thomas Hauß ◽  
Gernot Renger
Keyword(s):  
Electron Transfer ◽  
Photosystem Ii ◽  
Experimental Error ◽  
Room Temperature ◽  
Lamellar Spacing ◽  
Hydration Water ◽  
Major Peak ◽  
Repeat Distance ◽  
Ps Ii ◽  
Protein Motions

AbstractThe effect of dehydration on the lamellar spacing of photosystem II (PS II) membrane fragments from spinach has been investigated using neutron membrane diffraction at room temperature. The diffraction data reveal a major peak at a scattering vector Q of 0.049 Å−1 at a relative humidity (r.h.) of 90% corresponding to a repeat distance D of about 129 Å. Upon dehydration to 44% r.h., this peak shifts to about 0.060 Å−1 corresponding to a distance of 104.7±2.5 Å. Within experimental error, the latter repeat distance remains almost the same at hydration levels below 44% r.h. indicating that most of the hydration water is removed. This result is consistent with the earlier finding that hydration-induced conformational protein motions in PS II membrane fragments are observed above 44% r.h. and correlated with the onset electron transfer in PS II (Pieper et al. 2008, Eur. Biophys. J. 37: 657–663).

Microstructure of Sodium or Potassium Added Mg-Ni Eutectic Alloy

2014 ◽  
Vol 353 ◽  
pp. 228-232
Author(s):  
Hideyuki Saitoh ◽  
Y. Shiraishi
Keyword(s):  
Eutectic Alloy ◽  
Lamellar Spacing ◽  
Eutectic Structure ◽  
Water Quenching ◽  
Rapid Cooling ◽  
Cooling Speed ◽  
Sodium And Potassium ◽  
Refinement Effect ◽  
Potassium Addition

The microstructure of sodium or potassium added Mg-23.5 mass%Ni eutectic alloy was observed and the effect of sodium and potassium addition on the eutectic structure was investigated. All alloys showed the eutectic structure which composed of Mg phase and Mg2Ni phase, and no evidence of the sodium or potassium precipitation occurred. For the sodium added and furnace cooled alloy, the lamellar spacing in the eutectic structure became a little narrow and the Mg2Ni phase tends to become fragmentary as the amount of sodium increases. The sodium addition has a little effect for the refinement of the eutectic structure. For the potassium added and furnace cooled alloy, the lamellar spacing of the eutectic structure became clearly narrow even by the 0.1 mass% potassium additions. The morphology drastically varied in more than 0.5 mass% potassium added specimens, that is, the refinement and fragmentation of the Mg2Ni phase occurred. The potassium addition has a large effect for the refinement and the fragmentation of the Mg2Ni phase in the eutectic structure. For the water quenched specimens, the eutectic structure was extremely fine and globular shape with and without the additive element. The refinement effect by the water quenching is remarkably high even as the non-added specimen. The effect of sodium and potassium addition on the refinement of eutectic structure is not clear in the case of the rapid cooling speed during solidification.

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