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Online since: October 2010
Authors: Zhao Feng Wu, Xue Mei Wu, Lan Jian Zhuge, Yu Juan Cao
The number of Mn
pieces can be changed to adjust the content of Mn in the films.
Besides, it is considered that the increase of resistivity with Mn doping may be related to the following two facts: the first is that the doped Mn ions can depress the concentration of shallow donors (such as zinc interstitials and oxygen vacancies), which significantly suppresses the carrier concentration at room temperature and the second is that Mn atoms might accumulate at the grain boundary with increase of Mn content [17], which may produce electrical barriers and decrease the electron mobility.
XRD and Raman analysis show that ZnO doped with a moderate of Mn atoms might reinforce the grain growth, while excessive Mn dopant might degrade the grain growth.
Besides, it is considered that the increase of resistivity with Mn doping may be related to the following two facts: the first is that the doped Mn ions can depress the concentration of shallow donors (such as zinc interstitials and oxygen vacancies), which significantly suppresses the carrier concentration at room temperature and the second is that Mn atoms might accumulate at the grain boundary with increase of Mn content [17], which may produce electrical barriers and decrease the electron mobility.
XRD and Raman analysis show that ZnO doped with a moderate of Mn atoms might reinforce the grain growth, while excessive Mn dopant might degrade the grain growth.
Online since: September 2013
Authors: Xiao Jun Guo, Lei Lei Gao, Zhen Nan Li, Wang Tai Yong
Block diagram of data acquisition and processing unit
The function of various sensors are stated as follows: Speed sensor detects wheel revolutions per unit time for calculation of walking velocity, yield sensor of impulse type measures grain yield on-line; Capacitive humidity sensor measures grain moisture; Cutting table status sensor judges cutting operation by monitoring the lifting up and down.
Table 3 Content format id field length example illustrate id field Length example illustrate 1 Start character 3 TGY Fixed character identifier 2 ID 8 10000001 Vehicle number 3 Data encoding 10 0000262143 Information for fixed string 4 Fault information 10 0000000513 Binary said fault information 5 Longitude 10 123.456789 Said longitude 6 Dimension 9 12.345678 Said latitude 7 Positioning state 1 A A:orientation V: navigation 8 Longitude 1 E E:east longitude, W:west longitude 9 Latitude direction 1 S S:south latitude, N: latitude 10 Cooling water temperature 3 090 90℃ 11 Fuel level 3 020 20% 12 Engine speed 4 0700 700RPM 13 #1auger speed 4 0350 350RPM 14 2#1auger speed 4 0400 400RPM 15 Working hours 7 12345.6 12345.6h 16 Harvest time 6 1234.5 1234.5h 17 Hydraulic oil temperature 3 085 85℃ 18 Speed 4 12.3 12.3Km/h 19 Threshing cylinder speed 4 0200 200RPM 20 Cutting table tail speed 4 0100 100RPM 21 Status information table 4 0775 Binary said switch action 22 Terminator 1 #
Reliability related calculations, are carried out in accordance with the standard grain combine harvesters JB/T6287-2008 "Reliability Test Method for Evaluate the provisions of Section 9.2.
Table 3 Content format id field length example illustrate id field Length example illustrate 1 Start character 3 TGY Fixed character identifier 2 ID 8 10000001 Vehicle number 3 Data encoding 10 0000262143 Information for fixed string 4 Fault information 10 0000000513 Binary said fault information 5 Longitude 10 123.456789 Said longitude 6 Dimension 9 12.345678 Said latitude 7 Positioning state 1 A A:orientation V: navigation 8 Longitude 1 E E:east longitude, W:west longitude 9 Latitude direction 1 S S:south latitude, N: latitude 10 Cooling water temperature 3 090 90℃ 11 Fuel level 3 020 20% 12 Engine speed 4 0700 700RPM 13 #1auger speed 4 0350 350RPM 14 2#1auger speed 4 0400 400RPM 15 Working hours 7 12345.6 12345.6h 16 Harvest time 6 1234.5 1234.5h 17 Hydraulic oil temperature 3 085 85℃ 18 Speed 4 12.3 12.3Km/h 19 Threshing cylinder speed 4 0200 200RPM 20 Cutting table tail speed 4 0100 100RPM 21 Status information table 4 0775 Binary said switch action 22 Terminator 1 #
Reliability related calculations, are carried out in accordance with the standard grain combine harvesters JB/T6287-2008 "Reliability Test Method for Evaluate the provisions of Section 9.2.
Online since: October 2011
Authors: Zhong Tang Gao, Min Hua Zhang
The main reason of this happens is: when the other parameters are of the same conditions, with the output power increases, the role of unit time energy in the cladding layer material increases, the energy of laser beam to the coating increase, so that cladding is full phase transited, and also because the characteristics of laser processing is an instant effect, short duration of action, cooling speed, resulting in shorter growing grains, refined grains, resulting in significantly higher cladding microhardness.
But with the laser power increases, when the laser power exceeds a certain level, the power density over more and make matrix material melt, overheat, surface appear overheating organization structure, so that the surface hardness decreased, and secondly, with the laser power increases,the energy transfer to the cladding layer is increasing, speed up the role of mutual penetration between matrix and the cladding layer, dilution rate increased, a large number of elements in the matrix diffusion into the cladding layer, the microhardness of cladding layer are significantly reduced.
Through experiment compared analysis, no matter in microstructure or grain refinement, it Shows the best result when laser cladding process parameters are at P = 3.0 KW, V = 1000mm/min.
But with the laser power increases, when the laser power exceeds a certain level, the power density over more and make matrix material melt, overheat, surface appear overheating organization structure, so that the surface hardness decreased, and secondly, with the laser power increases,the energy transfer to the cladding layer is increasing, speed up the role of mutual penetration between matrix and the cladding layer, dilution rate increased, a large number of elements in the matrix diffusion into the cladding layer, the microhardness of cladding layer are significantly reduced.
Through experiment compared analysis, no matter in microstructure or grain refinement, it Shows the best result when laser cladding process parameters are at P = 3.0 KW, V = 1000mm/min.
Online since: August 2014
Authors: Jakob Klassen, Klaus Dilger, Thomas Nitschke-Pagel
Driven by that software engineers improved their product by means of user friendly interfaces, again leading to a broader number of users not only in the academic research area.
The focus of this research is on large-scale site connections of thick steel plates made of the fine grained construction steel grades, which have been derived from actual steel bridge constructions exactly as the investigated large scale components.
Experimental procedure The investigated steel grades have been derived from the most common construction steel grades used for highly stressed welded bridge structures, namely the normalised rolled fine-grain structural steel P355NL2 with a minimum yield strength of 355 MPa and in addition the P460NL with a minimum yield strength of 460 MPa.
Furthermore the plates are assumed to be stress free, since the steel grades are normalized fine grain steels.
The focus of this research is on large-scale site connections of thick steel plates made of the fine grained construction steel grades, which have been derived from actual steel bridge constructions exactly as the investigated large scale components.
Experimental procedure The investigated steel grades have been derived from the most common construction steel grades used for highly stressed welded bridge structures, namely the normalised rolled fine-grain structural steel P355NL2 with a minimum yield strength of 355 MPa and in addition the P460NL with a minimum yield strength of 460 MPa.
Furthermore the plates are assumed to be stress free, since the steel grades are normalized fine grain steels.
Online since: October 2002
Authors: Humberto Gracher Riella, C.D.G. de Borba, D.S. Morais
Journal Title and Volume Number (to be inserted by the publisher)
200 400 600 800 1000 1200
975
o
C
905 oC
871
o
C
B
C
A
DTA (µV)
Temperature (
o
C)
Fig. 1 - DTA curves of the A, B and C glasses.
The A-gc micrographs showed a non-homogeneous microstructure with a large grain size distribution (50 to 500 nm), while B-gc and C-gc showed a grain size inferior to 150 nm.
• The fine-grained microstructure obtained by using TiO2/ZnO or TiO2/SnO2 as nucleating agent, showed disk shaped crystals, with a medium diameter around 150 nm and a thickness of 30 nm. 20 30 40 50 60 (202) (004) (201) (002) B-gc C-gc A-gc Intensity (c.p.s.) 2 θ ( o ) Fig. 2 - X-ray patterns of A, B and C-gc (A, B and C glasses after heat treatments).
The A-gc micrographs showed a non-homogeneous microstructure with a large grain size distribution (50 to 500 nm), while B-gc and C-gc showed a grain size inferior to 150 nm.
• The fine-grained microstructure obtained by using TiO2/ZnO or TiO2/SnO2 as nucleating agent, showed disk shaped crystals, with a medium diameter around 150 nm and a thickness of 30 nm. 20 30 40 50 60 (202) (004) (201) (002) B-gc C-gc A-gc Intensity (c.p.s.) 2 θ ( o ) Fig. 2 - X-ray patterns of A, B and C-gc (A, B and C glasses after heat treatments).
Online since: August 2012
Authors: V.A.R. Henriques, Eduardo T. Galvani, O.C. Schichi, C.A.A. Cairo
Though a single layer coating enables a wide range of applications at various sectors of engineering, there is a growing number of applications where the properties of a single material is not sufficient.
Results and Discussions Ti-35Nb-7Zr-5Ta substrates The samples of Ti-35Nb-7Zr-5Ta alloy sintered at 1400ºC showed a microstructure composed basically of β-metastable phase grains.
A columnar grain structure perpendicular to the interface results from adjusted process parameters.
The multilayers TiN/ZrN have a morphological structure characteristic of a columnar epitaxial growth, containing some empty spaces between the grains.
Results and Discussions Ti-35Nb-7Zr-5Ta substrates The samples of Ti-35Nb-7Zr-5Ta alloy sintered at 1400ºC showed a microstructure composed basically of β-metastable phase grains.
A columnar grain structure perpendicular to the interface results from adjusted process parameters.
The multilayers TiN/ZrN have a morphological structure characteristic of a columnar epitaxial growth, containing some empty spaces between the grains.
Online since: November 2015
Authors: Corneliu Munteanu, Iulian Cucos, Constantin Mirea
A /00348 of 16.06.2011)
The shaft and turbine blades must withstand various complex applications (bend and torsion), cavitation and corrosion complex mechanical, chemical and biological, given the high cost of materials with high mechanical properties [3,4] required in aggressive environment and working turbine blades and complex manufacturing technology authors studied realization blades by steel C45-RO1.0503 fine grained hereditary, the heat treatment was applied to normalize for improving machinability by cutting followed by quenching and a high return in order to increase hardness and reduce state tensions and structural change in order to increase the toughness and wear resistance.
Parameters of heat treatment were designed with expert software based on mathematical model for predicting mechanical properties and structural piece heat treated and has as input the initial parameters of the process: the chemical composition of heat-treated steel, number and size blanks, the initial state of the structure of the piece, geometric and thermal conditions imposed piece and structural and mechanical properties obtained after heat treatment.
From the analysis of samples by electron microscopy SEM shows that if the heat treatment of pearlite grains are coarse classic uniformly distributed in the ferrite matrix therefore blade materials mechanical properties are reduced, the song has a good running, low durability and low mechanical strength.
If the heat treatment furnace realized with PID predictive structure of the material consists of fine pearlite crystalline grains uniformly distributed in the ferrite matrix, the mechanical properties are superior parts have a resistance high mechanical wear and high toughness.
Parameters of heat treatment were designed with expert software based on mathematical model for predicting mechanical properties and structural piece heat treated and has as input the initial parameters of the process: the chemical composition of heat-treated steel, number and size blanks, the initial state of the structure of the piece, geometric and thermal conditions imposed piece and structural and mechanical properties obtained after heat treatment.
From the analysis of samples by electron microscopy SEM shows that if the heat treatment of pearlite grains are coarse classic uniformly distributed in the ferrite matrix therefore blade materials mechanical properties are reduced, the song has a good running, low durability and low mechanical strength.
If the heat treatment furnace realized with PID predictive structure of the material consists of fine pearlite crystalline grains uniformly distributed in the ferrite matrix, the mechanical properties are superior parts have a resistance high mechanical wear and high toughness.
Online since: September 2011
Authors: Ru Yuan Yang, Huang Yu Chen, Shoou Jinn Chang, Min Hang Weng
In this structure, Sr2+ ions located at two kinds of unequivalent lattice sites, which coordination numbers are 9 and 10, respectively.
The shape of the particles is not much different from each other, but the grain size increases significantly as the concentrations of Li+ ions increasing.
Both the grain-boundary diffusion and volume diffusion play primary roles in neck growth, while surface diffusion gradually becomes the secondary mechanism [13].
The addition of Li+ ion not only improves the grain growth, but also acts as compensator to balance the charge valence when Sr2+ is substituted by Eu3+.
The shape of the particles is not much different from each other, but the grain size increases significantly as the concentrations of Li+ ions increasing.
Both the grain-boundary diffusion and volume diffusion play primary roles in neck growth, while surface diffusion gradually becomes the secondary mechanism [13].
The addition of Li+ ion not only improves the grain growth, but also acts as compensator to balance the charge valence when Sr2+ is substituted by Eu3+.
Online since: July 2015
Authors: Thomas Schmoelzer, Christian Gierl-Mayer, Moritz Boehm, Reinhard Simon
The evolution of the microstructure shows a decrease in number and size of the larger Cr particles as well as the growth of particles around the Mo agglomerates (see fig. 4b, 4c and 4d).
In fig. 8 a schematic of the proposed mechanism is shown: at elevated temperatures, Cr atoms move along grain boundaries and from areas with higher Laplace tensions (1).
On contact with Mo grains, the Cr atoms form a solid solution (2).
This could for instance be related to differences in surface or grain-boundary diffusion in this system.
In fig. 8 a schematic of the proposed mechanism is shown: at elevated temperatures, Cr atoms move along grain boundaries and from areas with higher Laplace tensions (1).
On contact with Mo grains, the Cr atoms form a solid solution (2).
This could for instance be related to differences in surface or grain-boundary diffusion in this system.
Online since: September 2016
Authors: Hong Liang Pan, Hai Ting Zhou, Qing Ming Wang, Jian Jun Chen
And the total number of elements gained after meshing in the model was about 60,000.
The most reasonable reason for the variation of electromagnetic properties would be that the different size and distribution of crystalline grain due to the entering of more silicon element.
It seems that this is due to the change in size and structure of crystalline grain and the area of grain boundary due to the different silicon element content.
The most reasonable reason for the variation of electromagnetic properties would be that the different size and distribution of crystalline grain due to the entering of more silicon element.
It seems that this is due to the change in size and structure of crystalline grain and the area of grain boundary due to the different silicon element content.