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Online since: January 2012
Authors: Jia Xuan Wang, Chun Li, Hua Qing Miao
Energy spectrum analysis for grain boundary and intracrystalline of liquid forging indicates that: liquid forging has micro-segregation, mainly Cu, Fe, Mg and Mn such elements in the form of compounds gathered at the grain boundaries, resulting in a grain and grain boundary ingredient uneven, where Cu and Fe segregation is especially remarkable.
The compounds band width is much thinner and the numbers much less in the part shape under the pressure of 90Mpa than that of pressure 80Mpa.
Thus, the segregation extent in the liquid die forging part shape under the pressure of 90MPa is lower than that of 80Mpa part, the grain also significantly more fine.
It can be obvious observed from the high and low organization figure that: liquid forging can forming flange blanks without shrinkage, porosity, loose and other casting defect; And improved the organization, refined the grain.
The latter is under the action of the pressure, the crystallization hard shell of the liquid metal or liquid forging part and cavity wall close contact and improve heat exchange between liquid metal and concave die, accelerate the solidification of the liquid forging parts, and because the effects of pressure increased the crystallization point of metal, increases the degree of supercooling, improve the nucleation rate, plus the dendrite crushing and fall off, the nucleation number also greatly increase, thus refined the grain, which has obvious grain refinement for thin liquid forgings.
The compounds band width is much thinner and the numbers much less in the part shape under the pressure of 90Mpa than that of pressure 80Mpa.
Thus, the segregation extent in the liquid die forging part shape under the pressure of 90MPa is lower than that of 80Mpa part, the grain also significantly more fine.
It can be obvious observed from the high and low organization figure that: liquid forging can forming flange blanks without shrinkage, porosity, loose and other casting defect; And improved the organization, refined the grain.
The latter is under the action of the pressure, the crystallization hard shell of the liquid metal or liquid forging part and cavity wall close contact and improve heat exchange between liquid metal and concave die, accelerate the solidification of the liquid forging parts, and because the effects of pressure increased the crystallization point of metal, increases the degree of supercooling, improve the nucleation rate, plus the dendrite crushing and fall off, the nucleation number also greatly increase, thus refined the grain, which has obvious grain refinement for thin liquid forgings.
Online since: June 2017
Authors: A.I. Gusev, O.A. Kozyreva, I.V. Osetkovskiy, N.A. Kozyrev, R.A. Gizatulin, A.V. Valueva
Size of former austenite grains conforms scale ranges № 5, 6.
While raising nickel content up to 0.33 – 0.54% austenite grain size didn’t change.
Sample number The contamination by nonmetallic inclusions, raiting Size of austenite gaine, raiting Size of martensite needles, mcm non-deformable silicates (fragile) Oxides spot 1 2b, 2a, 3a 1a 5, 6 7-10 2 1b, 2b, 3a 1a 5, 6 4-8 3 2b, 3a 1 a 5, 6 5-8 4 2b, 3а (1b) 1 а 6, 5 2-5 5 1b, 2b, 3a 1 a 6, 5 2-5 6 1б, 2b, 2a 1 a, 2a 6 2-4 7 1b, 2b, 3a 1 a 6 2-5 8 1b, 2b, 3a 1 a 6 2-4 Increasing the content of nickel up to 0.65% (sample №4) greatly grinds martensite needles, and reduce size of former austenite grains.
Size of former austenite grain conforms №6.
Per the results of calculations obtained dependencies, the adequacy of which was checked by actual values in index of the average approximation error: , (1) m - the number of observations; – calculated value of resulted index; – real value of resulted index.
While raising nickel content up to 0.33 – 0.54% austenite grain size didn’t change.
Sample number The contamination by nonmetallic inclusions, raiting Size of austenite gaine, raiting Size of martensite needles, mcm non-deformable silicates (fragile) Oxides spot 1 2b, 2a, 3a 1a 5, 6 7-10 2 1b, 2b, 3a 1a 5, 6 4-8 3 2b, 3a 1 a 5, 6 5-8 4 2b, 3а (1b) 1 а 6, 5 2-5 5 1b, 2b, 3a 1 a 6, 5 2-5 6 1б, 2b, 2a 1 a, 2a 6 2-4 7 1b, 2b, 3a 1 a 6 2-5 8 1b, 2b, 3a 1 a 6 2-4 Increasing the content of nickel up to 0.65% (sample №4) greatly grinds martensite needles, and reduce size of former austenite grains.
Size of former austenite grain conforms №6.
Per the results of calculations obtained dependencies, the adequacy of which was checked by actual values in index of the average approximation error: , (1) m - the number of observations; – calculated value of resulted index; – real value of resulted index.
Online since: January 2009
Authors: D. Lincot, J.F. Guillemoles, J. Kessler, J.P. Connolly, O. Ramdani, O. Roussel, D. Guimard, V. Bermudez, N* Naghavi, P.P. Grand, L. Parissi, J. Kurdi, O. Kerrec
The surface preparation
steps can permeate the pores and conformal CdS growth can be seen on the grain surfaces.
Therefore, it is likely that the grain boundaries are inverted, and have therefore n-type conductivity.
This is expected to result in a Voc loss of some 200 mV as Voc scales as the logarithm of the number of recombination centers.
One can now compare dense, vacuum deposited CuInS2 to porous, large grains, electrodeposited CuInS2 and to nanoporous DSC.
CdS deposition can be observed on the grain boundaries.
Therefore, it is likely that the grain boundaries are inverted, and have therefore n-type conductivity.
This is expected to result in a Voc loss of some 200 mV as Voc scales as the logarithm of the number of recombination centers.
One can now compare dense, vacuum deposited CuInS2 to porous, large grains, electrodeposited CuInS2 and to nanoporous DSC.
CdS deposition can be observed on the grain boundaries.
Online since: June 2025
Authors: Andrzej Trytek, Paweł Żurawski
The grain size affects the amount of oil carried during operation.
The final customer specifies the coating thickness, grain size, and grain quantity on the piston surface.
The grains are evenly distributed on the surface, without any gaps.
The grains are evenly distributed across the surface without any gaps.
Additionally, the difference is visible in the number of elements detected on the piston surface.
The final customer specifies the coating thickness, grain size, and grain quantity on the piston surface.
The grains are evenly distributed on the surface, without any gaps.
The grains are evenly distributed across the surface without any gaps.
Additionally, the difference is visible in the number of elements detected on the piston surface.
Online since: January 2015
Authors: Shao Min Zhang, Dong Yang Wang, Bao Yi Wang
Literature [3] idea of coarse-grained parallelism designs and implements the "satellite model" Particle swarm optimization.
LSSVM optimized by IPPSO Parallelization of PSO is divided into two different ways which are coarse-grained and fine-grained.
Literature [5] which uses idea of coarse-grained designs and implements "satellite" parallel particle swarm algorithm.
Core idea of Coarse-grained parallelism of PSO is to divide the population into several subgroups, and each subgroup separately conducts particle swarm algorithm.
The number of iterations is 2000 times. ,; ; , .
LSSVM optimized by IPPSO Parallelization of PSO is divided into two different ways which are coarse-grained and fine-grained.
Literature [5] which uses idea of coarse-grained designs and implements "satellite" parallel particle swarm algorithm.
Core idea of Coarse-grained parallelism of PSO is to divide the population into several subgroups, and each subgroup separately conducts particle swarm algorithm.
The number of iterations is 2000 times. ,; ; , .
Online since: March 2023
Authors: Kutaiba Al-Marzoki, Wisam Naji Hasan, Mohammed Naji Al-Aaraji
Doping with La+3 causes reduction in grain size, whereas Sc+3 increase the grain size.
Also, it is found reduction in the grain size after doping.
As a result develops the relaxor actions in a number of perovskites such as Pb0.78Ba0.22Sc0.5Ta0.5O3 [26] and PbSc0.5Nb(1−x)/2Tax/2O3 (PSNT) with 0 ≤ x ≤ 1 [27].
Langman et al. [30] ascribed this grain size decrease to the solid solution impurity drag mechanism, which says that the presence of the La3+ ion concentration gradient at grain boundaries causes hindering of grain boundary mobility and subsequently leads to slow grain growth.
It shows a big reduction in grain size.
Also, it is found reduction in the grain size after doping.
As a result develops the relaxor actions in a number of perovskites such as Pb0.78Ba0.22Sc0.5Ta0.5O3 [26] and PbSc0.5Nb(1−x)/2Tax/2O3 (PSNT) with 0 ≤ x ≤ 1 [27].
Langman et al. [30] ascribed this grain size decrease to the solid solution impurity drag mechanism, which says that the presence of the La3+ ion concentration gradient at grain boundaries causes hindering of grain boundary mobility and subsequently leads to slow grain growth.
It shows a big reduction in grain size.
Online since: May 2007
Authors: Shi Qiong Li, Jian Wei Zhang, Yun Jun Cheng, Xiao Bo Liang
Such discontinuous yielding characteristics has also been observed in a large number of bcc
materials [10].
This microstructure exhibits newly formed recrystallization grains with irregular grain boundaries.
At the critical strain, the migration of a large number of interfaces leads to flow softening.
On the other hand, for the material with high stacking fault energy (SFE), the grain growth (big angle grain boundaries migration) rate is slow, a steady-state stress-strain curves occurs.
Fig.4 (c) shows a typical microstructure which includes a number of the local slip bands, some of which cross the grain boundaries, indicating the flow instability occur in the form of adiabatic shear bands.
This microstructure exhibits newly formed recrystallization grains with irregular grain boundaries.
At the critical strain, the migration of a large number of interfaces leads to flow softening.
On the other hand, for the material with high stacking fault energy (SFE), the grain growth (big angle grain boundaries migration) rate is slow, a steady-state stress-strain curves occurs.
Fig.4 (c) shows a typical microstructure which includes a number of the local slip bands, some of which cross the grain boundaries, indicating the flow instability occur in the form of adiabatic shear bands.
Online since: August 2018
Authors: Ai Xia Chen, Jie Guang Song, Mei Hua Chen, Jin Shi Li, Chao Yang, Ge Xiong, Hui Min Sun, Xue Yang, Lin Chen
Effect of Synthetic Technology on the Properties of Co2O3 PowderWe have edited your paper and made a number of suggestions for improvement, which can be viewed in this TRACKED file.
A small number of hexagonal sheets with larger particle size of approximately State the particle size.
The longer the reaction time was, the more time the grains had for growth and the more complete the grains were.
Shorter reaction time indicates shorter time for grain growth, resulting in the incomplete formation of a grain and the formation of smaller particles with irregular morphology.
This phenomenon enhanced the nucleation rate and grain size.
A small number of hexagonal sheets with larger particle size of approximately State the particle size.
The longer the reaction time was, the more time the grains had for growth and the more complete the grains were.
Shorter reaction time indicates shorter time for grain growth, resulting in the incomplete formation of a grain and the formation of smaller particles with irregular morphology.
This phenomenon enhanced the nucleation rate and grain size.
Online since: January 2026
Authors: Ming Jen Tan, Jia Zheng
Introduction
Aluminum foam sandwich(AFS) preform is a porous metal made by introducing a large number of near spherical pores into aluminum alloy[1,2].
The number of grid division of the model is 64549, and the grid quality is as high as 0.7.
The results show that the average grain sizes of NZ and HAZ after FSW are 1.3μm and 3.8 μm.
Furthermore, there are some ultrafine grains in NZ.
Therefore, it can be concluded that FSW can further refine the grain of the material.
The number of grid division of the model is 64549, and the grid quality is as high as 0.7.
The results show that the average grain sizes of NZ and HAZ after FSW are 1.3μm and 3.8 μm.
Furthermore, there are some ultrafine grains in NZ.
Therefore, it can be concluded that FSW can further refine the grain of the material.
Online since: July 2006
Authors: Tadashi Minoda, Hideo Yoshida, M. Asano
The grain sizes and the size distributions of the second phase particles were measured by optical
microscopy.
Results Figure 1 shows the microstructures of the T4 samples and Fig. 2 shows the influence of the iron content on the grain size.
The grain size of the samples with the higher iron contents became smaller.
Table 2 shows the relationship between the iron content, number of second phase particles, number of shear bands and bendability.
The grain size became smaller with an increasing iron content due to an increase in the β-AlFeSi particles. 2.
Results Figure 1 shows the microstructures of the T4 samples and Fig. 2 shows the influence of the iron content on the grain size.
The grain size of the samples with the higher iron contents became smaller.
Table 2 shows the relationship between the iron content, number of second phase particles, number of shear bands and bendability.
The grain size became smaller with an increasing iron content due to an increase in the β-AlFeSi particles. 2.