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Online since: August 2013
Authors: Michael Sсheffler, Mazhyn Skakov, Lyaila B. Bayatanova
After carbonitriding with rapid acsess and subsequent hardening, surface steel has fine-grained structure because martensite (A → M) transformation does not take place until the end, and steel contains decay products.
In the first zone, alongside with the residual austenite, large number of carbonitrides have been formed.
In moving deeper into the layer, number and size of carbide and nitride particles decreases.
Number 11
In the first zone, alongside with the residual austenite, large number of carbonitrides have been formed.
In moving deeper into the layer, number and size of carbide and nitride particles decreases.
Number 11
Online since: July 2006
Authors: B.M. Jović, V. Maksimović, M.G. Pavlović, Vlada D. Jović
With decrease
of Ni2+/Co
2+ ions ratio among 2D fern-like dendrites, 3D dendrites and different agglomerates of a
size of about 100 µm, being either compact (typical for pure Co powder) or composed of a large
number of small 3D dendrites on their surface were obtained.
At a relatively low current density of 3.3 A dm-2, individual coarse-grained particles were formed, while at higher current density of 10.0 A dm-2 gradual coalescence and refinement of particles to form nodular clusters was achieved.
With the decrease of Ni 2+/Co 2+ ions ratio among 2D fern-like dendrites, agglomerates of the size of about 100 µm, composed of a large number of small 3D dendrites on their surface were obtained.
At the lowest Ni 2+/Co 2+ concentration ratio, three types of particles were detected in the Ni-Co powder: 2D fern-like dendrites, compact agglomerates typical of pure Co powder and smaller agglomerates composed of a large number of 3D dendrites.
At a relatively low current density of 3.3 A dm-2, individual coarse-grained particles were formed, while at higher current density of 10.0 A dm-2 gradual coalescence and refinement of particles to form nodular clusters was achieved.
With the decrease of Ni 2+/Co 2+ ions ratio among 2D fern-like dendrites, agglomerates of the size of about 100 µm, composed of a large number of small 3D dendrites on their surface were obtained.
At the lowest Ni 2+/Co 2+ concentration ratio, three types of particles were detected in the Ni-Co powder: 2D fern-like dendrites, compact agglomerates typical of pure Co powder and smaller agglomerates composed of a large number of 3D dendrites.
Online since: January 2015
Authors: Wojciech Labuda, Adam Charchalis
In addition, the influence of the burnisher passes number on the friction factor was determined.
Burnishing process enables surface working at high dimensional precision (the accuracy class 7 and 6) which gives the following advantages [4, 5]: - ability to achieve high smoothness (Ra = 0.32 – 0.04 µm) of the surface and high bearing surface of roughness profile 90%, - increasing the surface hardness, - increasing resistance to surface fatigue and volumetric fatigue, - increasing resistance to abrasive wear and scuffing, - lack of abrasive grain, chips, sharp and hard built-up edge fragments on burnished surface, - possibility of using burnish tools on universal lathes ( the concept of one stand working), - eliminating or limiting the time consuming operations such as honing, lapping, grinding and polishing, - ability to eliminate heat treatment in specific cases, - high process efficiency (one working transition of a tool) and reduction of production costs, - high durability of burnishing tools.
The influence of the number of burnishing passes on surface roughness and surface layer hardness was also determined within the research.
Labuda, Estimation of the influence of passes number burnishing tool on ships pumps shafts surface layers strengthening and roughness changes, Journal of KONES Powertrain and Transport, Zakopane 16(4) (2009) 43–50
Burnishing process enables surface working at high dimensional precision (the accuracy class 7 and 6) which gives the following advantages [4, 5]: - ability to achieve high smoothness (Ra = 0.32 – 0.04 µm) of the surface and high bearing surface of roughness profile 90%, - increasing the surface hardness, - increasing resistance to surface fatigue and volumetric fatigue, - increasing resistance to abrasive wear and scuffing, - lack of abrasive grain, chips, sharp and hard built-up edge fragments on burnished surface, - possibility of using burnish tools on universal lathes ( the concept of one stand working), - eliminating or limiting the time consuming operations such as honing, lapping, grinding and polishing, - ability to eliminate heat treatment in specific cases, - high process efficiency (one working transition of a tool) and reduction of production costs, - high durability of burnishing tools.
The influence of the number of burnishing passes on surface roughness and surface layer hardness was also determined within the research.
Labuda, Estimation of the influence of passes number burnishing tool on ships pumps shafts surface layers strengthening and roughness changes, Journal of KONES Powertrain and Transport, Zakopane 16(4) (2009) 43–50
Online since: February 2011
Authors: Chun Quan Li, Chun Yang Hu, Yan Wei Wang
Diverse-grained information such as the abstract, description, interface, packages have been put forward on basis of resource virtualization technology of manufacturing grid in order to implement resource virtualization.
And essential attribute includes mark number, name, supplier, model, category and so on; Performance properties is a description of resource performance parameters and different types of resources have different performance; And it also has resource trading mode, cost attribute and some outward appearance size and so on.
And essential attribute includes mark number, name, supplier, model, category and so on; Performance properties is a description of resource performance parameters and different types of resources have different performance; And it also has resource trading mode, cost attribute and some outward appearance size and so on.
Online since: February 2008
Authors: Ming Xing Ai, Hong Xiang Zhai, Zhen Ying Huang, Yi Wang, Hong Bing Zhang
It was found that the molten Cu
accelerating the decomposition of Ti3AlC2, inducing the interfacial exfoliation to generate, and forming a
sub-micro-layered structure making up of TiCx layers and Cu-Al alloy layers within a Ti3AlC2 grain.
Because the good ductility of the Cu-Al alloy, the meshes of the net were elongated along the direction of tensile stress, and consequently formed a larger number of dimples on the fracture surface.
Because the good ductility of the Cu-Al alloy, the meshes of the net were elongated along the direction of tensile stress, and consequently formed a larger number of dimples on the fracture surface.
Online since: December 2014
Authors: Petr Zelený, Jiří Šafka, Michal Ackermann, Martin Lachman, Petr Keller
The specimens were also subjected to material tests to reveal its inner structure, quality of a grain and chemical composition of the material.
For further differentiation between the specimens, the ones with the same alignment are marked with the same number and each pair is distinguished by alphabetical suffix (Figure 3).
For further differentiation between the specimens, the ones with the same alignment are marked with the same number and each pair is distinguished by alphabetical suffix (Figure 3).
Online since: October 2006
Authors: Richard E. Riman, Wojciech L. Suchanek
The growing number of scientific papers on hydrothermal synthesis of
ceramic powders, which almost quadrupled between 2000 and 2004 (Fig. 1a), illustrates the rising
interest in this area, with China, Japan, and USA publishing most extensively (Fig. 1b).
(a) Number of papers on hydrothermal processing of ceramic powders published between 1989-2005 vs. all materials science-related papers on hydrothermal technology [4]; (b) geographical distribution of the research on hydrothermal processing of ceramic powders (1989-2005).
Sawyer's products line of the ĮAl2O3 powders called DiamoCor, comprises both undoped and Mn or Cr-doped compositions with the following grain sizes: 40 ȝm, 20-25 ȝm, 10 ȝm, 6 ȝm, 3 ȝm, 1 ȝm, and 100-250 nm.
Representative corundum powders with a 10 ȝm grain size are shown in Fig. 6a.
The picture reveals typical as-synthesized powder, with uniform particle size distribution and well-defined crystal faces in each grain, which is a single crystal of the Į-Al2O3 phase.
(a) Number of papers on hydrothermal processing of ceramic powders published between 1989-2005 vs. all materials science-related papers on hydrothermal technology [4]; (b) geographical distribution of the research on hydrothermal processing of ceramic powders (1989-2005).
Sawyer's products line of the ĮAl2O3 powders called DiamoCor, comprises both undoped and Mn or Cr-doped compositions with the following grain sizes: 40 ȝm, 20-25 ȝm, 10 ȝm, 6 ȝm, 3 ȝm, 1 ȝm, and 100-250 nm.
Representative corundum powders with a 10 ȝm grain size are shown in Fig. 6a.
The picture reveals typical as-synthesized powder, with uniform particle size distribution and well-defined crystal faces in each grain, which is a single crystal of the Į-Al2O3 phase.
Online since: May 2021
Authors: V.N. Yarmakovsky, D. Kadiev
Geometric parameters in the analog model (size, number, inhomogeneity of pores, shape of inclusions, etc.) were assigned taking into account experimental data on the investigations of the SLAC and NWC macrostructure.
Physical parameters (strength, modulus of elasticity, etc.) were set for inclusions in the form of equations у = f(rm), obtained by correlation analysis, and for the matrix – у = f[C; (W/C)tr; Rc] obtained by experimental planning methods (here y is the property under researches, rm is the average grain density of the coarse aggregate, kg/m3; C is the concentration of hardened cement paste in mortar, rel. units.; (W/C)tr – true water-cement ratio of concrete, rel. units; W – mixing water of concrete mix minus water absorbed by porous aggregate; Rc – cement activity, MPa).
Influence of the macrostructure parameters (n) of SLAC and equal strength NWC on the strength (q) under axial compression, based on the results of computational experiments. 1 – inhomogeneity of SLAC inclusions; 1’ – inhomogeneity of NWC inclusions; 2 – strength of the SLAC contact zone; 2’ – strength of the NWC contact zone; 3 – width of the SLAC contact zone; 4, 5 – respectively the coefficient of the of the SLAC aggregate grains shape and their size; 6 – pore size of SLAC cement matrix; 6’ – pore size of NWC cement matrix; 7 – pore volume of SLAC.
Based on the results of the figure 1 review, with the use of the ranking method, which is one of the most effective methods of expert analysis, it is possible to estimate the efficiency of the influence indicators of concrete macrostructure various parameters on its strength and frost resistance consequently in order to reduce the value of these indicators: the strength of the contact zone of the hardened cement paste (HCP) and coarse aggregate, the grain size of coarse aggregate (inclusions), the pores size and their volume in concrete body, heterogeneity of inclusions.
The test base – the number of concrete freezing and thawing cycles was selected no more than 10, based on the actual operating conditions of reinforced concrete tanks for storing liquefied natural gases (LNG): filling of LNG into tanks for loading into gas tankers, possible partial or complete emptying of tanks if necessary for repair work.
Physical parameters (strength, modulus of elasticity, etc.) were set for inclusions in the form of equations у = f(rm), obtained by correlation analysis, and for the matrix – у = f[C; (W/C)tr; Rc] obtained by experimental planning methods (here y is the property under researches, rm is the average grain density of the coarse aggregate, kg/m3; C is the concentration of hardened cement paste in mortar, rel. units.; (W/C)tr – true water-cement ratio of concrete, rel. units; W – mixing water of concrete mix minus water absorbed by porous aggregate; Rc – cement activity, MPa).
Influence of the macrostructure parameters (n) of SLAC and equal strength NWC on the strength (q) under axial compression, based on the results of computational experiments. 1 – inhomogeneity of SLAC inclusions; 1’ – inhomogeneity of NWC inclusions; 2 – strength of the SLAC contact zone; 2’ – strength of the NWC contact zone; 3 – width of the SLAC contact zone; 4, 5 – respectively the coefficient of the of the SLAC aggregate grains shape and their size; 6 – pore size of SLAC cement matrix; 6’ – pore size of NWC cement matrix; 7 – pore volume of SLAC.
Based on the results of the figure 1 review, with the use of the ranking method, which is one of the most effective methods of expert analysis, it is possible to estimate the efficiency of the influence indicators of concrete macrostructure various parameters on its strength and frost resistance consequently in order to reduce the value of these indicators: the strength of the contact zone of the hardened cement paste (HCP) and coarse aggregate, the grain size of coarse aggregate (inclusions), the pores size and their volume in concrete body, heterogeneity of inclusions.
The test base – the number of concrete freezing and thawing cycles was selected no more than 10, based on the actual operating conditions of reinforced concrete tanks for storing liquefied natural gases (LNG): filling of LNG into tanks for loading into gas tankers, possible partial or complete emptying of tanks if necessary for repair work.
Online since: June 2009
Authors: Pradyot Datta
Liou et al. [95] reported variation of grain size with sintering time and temperature.
In fact there is a linear correlation between grain boundary conductivity and porosity.
Moreover, this technique produces large grains (1-10 µm) which are clearly a disadvantage as uncontrolled crystalline growth can occur, which could induce chemical and grain-size non-uniformity [102].
Composite anode The material selection for an SOFC anode is determined by a number of factors.
The transport of oxide ions within the electrode material is beneficial concerning the number of possible reaction pathways.
In fact there is a linear correlation between grain boundary conductivity and porosity.
Moreover, this technique produces large grains (1-10 µm) which are clearly a disadvantage as uncontrolled crystalline growth can occur, which could induce chemical and grain-size non-uniformity [102].
Composite anode The material selection for an SOFC anode is determined by a number of factors.
The transport of oxide ions within the electrode material is beneficial concerning the number of possible reaction pathways.
Online since: February 2013
Authors: Chih Ming Chiu, Shao Shin Hung, Kuo Kuang Fan, Jyh Jong Tsay
First, the number common elements occur in the two sequences.
Second, function g is responsible to count the number of non-common elements.
Table 1 Information on radius and average number of objects in one view.
This also helps to explore the hidden relationships and estimate future fine-grained placements, leveraging the most effective predictive mechanism for each situation.
Fig. 4 Comparison of different algorithms on the number of objects retrieved.
Second, function g is responsible to count the number of non-common elements.
Table 1 Information on radius and average number of objects in one view.
This also helps to explore the hidden relationships and estimate future fine-grained placements, leveraging the most effective predictive mechanism for each situation.
Fig. 4 Comparison of different algorithms on the number of objects retrieved.