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Online since: May 2014
Authors: Kenji Higashi, Yorinobu Takigawa, Isao Matsui
The electrodeposited alloys had a nanocrystalline structure with grain sizes of approximately 20 nm and a stronger (111) texture.
Introduction Electrodeposition has been developed as a fabrication process for bulk nanocrystalline metals with grain size of less than 100 nm [1-6].
There have been a number of papers that have addressed the tensile properties of electrodeposited bulk nanocrystalline metals.
X-ray diffraction (XRD, RIGAKU Ultimate IV) analysis was performed using Cu Ka radiation to estimate the grain size and examine the crystalline texture.
The grain sizes of samples LS45 and HS45 estimated using the XRD peak width and Scherre’s equation were approximately 20 nm.
Introduction Electrodeposition has been developed as a fabrication process for bulk nanocrystalline metals with grain size of less than 100 nm [1-6].
There have been a number of papers that have addressed the tensile properties of electrodeposited bulk nanocrystalline metals.
X-ray diffraction (XRD, RIGAKU Ultimate IV) analysis was performed using Cu Ka radiation to estimate the grain size and examine the crystalline texture.
The grain sizes of samples LS45 and HS45 estimated using the XRD peak width and Scherre’s equation were approximately 20 nm.
Online since: February 2014
Authors: Hong Jie Pei, Chong Lue Hua, Juan Huang, Gui Cheng Wang, Jun Feng Zou
The reason is that with the increase of grinding speeds, the cutting grains’ number Nd increases in unit time.
Therefore the heat pulse number increases, and the thermal stress enhances, resulting in the decrease of the residual stress in the grind- hardening surface.
The increase of stress depth is due to the increase of martensitic transformation volume number, caused by the increase of grind-hardening layer depth.
This is because the grains’ number participated in the cutting process is increased in unit time, so the thermal pulse number increases, and the scope of the workpiece expansion becomes larger.
This is because the grains’ number participated in the cutting process is increased in unit time, so the thermal pulse number increases, and the scope of the workpiece expansion becomes larger.
Therefore the heat pulse number increases, and the thermal stress enhances, resulting in the decrease of the residual stress in the grind- hardening surface.
The increase of stress depth is due to the increase of martensitic transformation volume number, caused by the increase of grind-hardening layer depth.
This is because the grains’ number participated in the cutting process is increased in unit time, so the thermal pulse number increases, and the scope of the workpiece expansion becomes larger.
This is because the grains’ number participated in the cutting process is increased in unit time, so the thermal pulse number increases, and the scope of the workpiece expansion becomes larger.
Online since: January 2016
Authors: Stan Veprek, Pavel Holubar, Maritza Veprek-Heijman
Therefore the grain size of 10-15 nm is called the “strongest size” [13] (see also Fig. 6 in Ref. [14]).
In Ref. [7] one can find a number of applications which we shall not repeat here.
Therefore the hardness enhancement to 50 GPa found experimentally is only due to the grain refinement.
For these reasons the number of systems which may form superhard nanocomposites with strengthened interfacial layer is limited.
Further research may somewhat increase the number of such systems, but hardly in any “revolutionary” manner.
In Ref. [7] one can find a number of applications which we shall not repeat here.
Therefore the hardness enhancement to 50 GPa found experimentally is only due to the grain refinement.
For these reasons the number of systems which may form superhard nanocomposites with strengthened interfacial layer is limited.
Further research may somewhat increase the number of such systems, but hardly in any “revolutionary” manner.
Online since: August 2017
Authors: Brigitte Bacroix, Alain Lodini, Marcin Wronski, Andrzej Baczmański, Krzysztof Wierzbanowski, Sebastian Wroński, Mariusz Jędrychowski, Jacek Tarasiuk
For example the average grain size, as determined from EBSD measurements, is higher in the sample stretched along rolling direction.
In last years a number of experimental and theoretical works on titanium deformed in tensile test were published [6-10].
This difference between hardening curves were observed in a number of repeated tensile tests and the same result was found.
c) In the sample stretched along TD also a smaller average grain size, smaller lattice distortion and lower coherent domain size are observed.
Acknowledgements This work was supported by the Polish National Centre for Science (NCN) under decision number DEC-2013/11/B/ST3/03787.
In last years a number of experimental and theoretical works on titanium deformed in tensile test were published [6-10].
This difference between hardening curves were observed in a number of repeated tensile tests and the same result was found.
c) In the sample stretched along TD also a smaller average grain size, smaller lattice distortion and lower coherent domain size are observed.
Acknowledgements This work was supported by the Polish National Centre for Science (NCN) under decision number DEC-2013/11/B/ST3/03787.
Online since: July 2010
Authors: Eun Zoo Park, Ho Jun Chae, Hyo Jin Ban, Yeong Seok Yoo
Also, periodic growth rate and development of leaves was satisfactory as natural soil and growth and
numbers of pollens were good.
Results and discussion 3.1 Analyzing the characteristics of artificial soil While domestic soil grain has generally average specific gravity of 2.66g/cm3, bulk density of 1.23g/cm3 and the specific gravity of soil grain in rice field, patch, forest is respectively 2.62, 2.64, 2.67g/cm3, the bulk density of artificial soil is only 0.75, 0.61, 0.55 g/cm3 with very light weight.
The below Fig.1 shows the number of total leaves created when investigating the flowering time of Arabidopsis thaliana.
It indicates the number of leaves of Arabidopsis thaliana growing in natural soil and artificial soil by date and it means the growth speed of Arabidopsis thaliana.
The number of hemocytes was 520×104~591×104 in natural soil and 24×104~600× 104 in artificial soil.
Results and discussion 3.1 Analyzing the characteristics of artificial soil While domestic soil grain has generally average specific gravity of 2.66g/cm3, bulk density of 1.23g/cm3 and the specific gravity of soil grain in rice field, patch, forest is respectively 2.62, 2.64, 2.67g/cm3, the bulk density of artificial soil is only 0.75, 0.61, 0.55 g/cm3 with very light weight.
The below Fig.1 shows the number of total leaves created when investigating the flowering time of Arabidopsis thaliana.
It indicates the number of leaves of Arabidopsis thaliana growing in natural soil and artificial soil by date and it means the growth speed of Arabidopsis thaliana.
The number of hemocytes was 520×104~591×104 in natural soil and 24×104~600× 104 in artificial soil.
Online since: January 2019
Authors: Lei Gang Wang, Yao Huang, Lei Liu, Xiang Ma
The number of the deformation zone and the measured residual stress of the zinc layer are shown in Table 3.
A large number of grains in the surface of the substrate are elongated.
The internal grains undergo severe deformation, and the sediments at the grain boundaries increase significantly.
The grains and their orientations in the middle layer are not so obvious, and they tend to infiltrate each other.
Acknowledgement This work is supported by the National Natural Science Foundation of China (project numbers: 51275216 and 51775249).
A large number of grains in the surface of the substrate are elongated.
The internal grains undergo severe deformation, and the sediments at the grain boundaries increase significantly.
The grains and their orientations in the middle layer are not so obvious, and they tend to infiltrate each other.
Acknowledgement This work is supported by the National Natural Science Foundation of China (project numbers: 51275216 and 51775249).
Online since: December 2010
Authors: Hai Bo Qi, De Liang Ren, Ming Jun Zheng
The positive scanning datum about odd-numbered filling lines and reverse scanning datum about even-numbered filling lines are stored in one document.
In the positive scanning, the electron beam just scans the odd-numbered filling lines (line 1, 3, 5, 7 and 9 in Fig. 2 (b)); in the reverse scanning, the electron beam scans the even-numbered filling lines (line 8, 6, 4 and 2 in Fig. 2 (b)).
Figure 4 (c) was the microstructure of the tensile specimen, which shown a fine-grain microstructure better than that of cast Ti-6Al-4V.
The grain of Ti-6Al-4V made by EBSM has a lamellar α-phase and β-phase.
The grain has no obvious growth direction as high temperature and low conductivity of Ti-6Al-4V powder.
In the positive scanning, the electron beam just scans the odd-numbered filling lines (line 1, 3, 5, 7 and 9 in Fig. 2 (b)); in the reverse scanning, the electron beam scans the even-numbered filling lines (line 8, 6, 4 and 2 in Fig. 2 (b)).
Figure 4 (c) was the microstructure of the tensile specimen, which shown a fine-grain microstructure better than that of cast Ti-6Al-4V.
The grain of Ti-6Al-4V made by EBSM has a lamellar α-phase and β-phase.
The grain has no obvious growth direction as high temperature and low conductivity of Ti-6Al-4V powder.
Online since: January 2013
Authors: Tian Dong Xia, Wen Jun Zhao, Wan Wu Ding, Jiang Tao Zhu
In the process when late model Al-Ti-C alloy ingot is extruded into wire rod, a large number of intermediate alloy scrap will be produced.
Since experimental alloys contain a large number of second phase particles of TiAl3 and TiC, which is convenient for the observation of the interaction between and distribution of second phase particles, thus it will be conducive to the experimental analysis.
At the same time, a large number of small black particle groups occur on the α-Al grain boundaries.
Metallograph of Al-Ti-C after remelted at 730˚C: (1) 30 minutes; (2) 60 minutes; (3)120 minutes; (4) 180 minutes;(5)microscopic structure of the TiC particles in grain boundary.
and during the solidification process they are pushed by α-Al toward the grain boundaries.
Since experimental alloys contain a large number of second phase particles of TiAl3 and TiC, which is convenient for the observation of the interaction between and distribution of second phase particles, thus it will be conducive to the experimental analysis.
At the same time, a large number of small black particle groups occur on the α-Al grain boundaries.
Metallograph of Al-Ti-C after remelted at 730˚C: (1) 30 minutes; (2) 60 minutes; (3)120 minutes; (4) 180 minutes;(5)microscopic structure of the TiC particles in grain boundary.
and during the solidification process they are pushed by α-Al toward the grain boundaries.
Online since: January 2009
Authors: Ahmet Atasoy, F.R. Sale
The
formation of carbon monoxide was also affected on the reduction of chromite spinel, especially
around imperfections of grain where porosity, cracks and fractures act as diffusion channel for the
reducing gas.
Whilst the metallic phases are mainly collected around the grain.
It can also be expected that these metallic phases collect within the grain, if there is enough volume in the particle (Figs. 4c and d).
The reduction of chromium starts at the iron carbide interface and on the surface of the grain through the centre of the spinel.
A number of iron and chromium carbide phases, Fe3C, Cr3C2, (Cr, Fe)7C3, were produced between 1100 C and 1500 C.
Whilst the metallic phases are mainly collected around the grain.
It can also be expected that these metallic phases collect within the grain, if there is enough volume in the particle (Figs. 4c and d).
The reduction of chromium starts at the iron carbide interface and on the surface of the grain through the centre of the spinel.
A number of iron and chromium carbide phases, Fe3C, Cr3C2, (Cr, Fe)7C3, were produced between 1100 C and 1500 C.
Online since: June 2016
Authors: Wahyono Suprapto, Widia Setiawan, Djarot B. Darmadi, Rudy Sunoko
The nugget zone (NZ), microstructure of was characterized by fine grains.
Grains in NZ could become larger as the welding tool rotational speed increased or the traverse speed decreased.
In thermo mechanically affected zone (TMAZ) of both skin and stringer, grains with highly deformed structure was obtained.
The microstructures Nugget Zone, Themomechanically Affected Zone, Heat Affected Zone , and parent metal its same grain size so fine recritallized smoothest.
The hardness was measured two a cross section is shown Fig. 7 Fig. 7 Micro hardness Vickers Number 3 mm Indentor/ 500μm B A The welding joint Fig. 8 Measuring Micro Hardness The Micro Hardness value can be seen its same , because homogenious micro structure phase and grain size number.
Grains in NZ could become larger as the welding tool rotational speed increased or the traverse speed decreased.
In thermo mechanically affected zone (TMAZ) of both skin and stringer, grains with highly deformed structure was obtained.
The microstructures Nugget Zone, Themomechanically Affected Zone, Heat Affected Zone , and parent metal its same grain size so fine recritallized smoothest.
The hardness was measured two a cross section is shown Fig. 7 Fig. 7 Micro hardness Vickers Number 3 mm Indentor/ 500μm B A The welding joint Fig. 8 Measuring Micro Hardness The Micro Hardness value can be seen its same , because homogenious micro structure phase and grain size number.