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Online since: February 2019
Authors: L.V. Radionova, Viacheslav V. Shirokov, Sergei R. Faizov, Maxim A. Zhludov
Also the reason of tool stability reduction at high-speed drawing can be increasing resistance to plastic metal deformation by means of increase in strain rate [4].
Given data Mother pipe diameter, mm 6.50 Diameter of ready wire, mm 3.00 Temporary stock tear resistance, MPa 1158 Carbon content, % 0.70 Calculated results Pass number 1 2 3 4 5 6 7 Drawing route 5.993 5.293 4.674 4.128 3.692 3.303 3 Degree of single deformation, % 15 22 22 22 20 20 17.48 Total deformation degree, % 78.7 Reduction ratio 1.176 1.282 1.282 1.282 1.250 1.250 1.212 Total reduction 4.69 Temporary tear resistance, MPa 1206 1283 1366 1453 1536 1625 1705 Wire-die half-angle, deg. 6 6 6 6 4 4 4 Friction coefficient 0.030 0.030 0.030 0.030 0.030 0.030 0.030 Drawing pressure, N/mm2 342.6 498.3 530.2 564.2 557.1 589.1 546.8 Drawing amplification, N 9658 10956 9094 7547 5963 5044 3863 Drawing speed, m/min 120 124 159 198 253 319 398 Power consumed by electric drives, kWt 21.46 25.16 26.78 27.67 27.94 29.8 28.47 Electric energy consumption, kWt/h 143.56 Productivity, t/h 1.316 With a help of a mathematical model of temperature speed drawing mode on FIFO drawing mills wire temperature
Conclusion From this perspective to achieve drawing speeds stipulated by the drawing machine data sheet and increase stability of the drawing tool the approach to selecting the following process parameters on modern drawing machines must be changed: the single deformation (strain) degree and wire-die half-angle.
Given data Mother pipe diameter, mm 6.50 Diameter of ready wire, mm 3.00 Temporary stock tear resistance, MPa 1158 Carbon content, % 0.70 Calculated results Pass number 1 2 3 4 5 6 7 Drawing route 5.993 5.293 4.674 4.128 3.692 3.303 3 Degree of single deformation, % 15 22 22 22 20 20 17.48 Total deformation degree, % 78.7 Reduction ratio 1.176 1.282 1.282 1.282 1.250 1.250 1.212 Total reduction 4.69 Temporary tear resistance, MPa 1206 1283 1366 1453 1536 1625 1705 Wire-die half-angle, deg. 6 6 6 6 4 4 4 Friction coefficient 0.030 0.030 0.030 0.030 0.030 0.030 0.030 Drawing pressure, N/mm2 342.6 498.3 530.2 564.2 557.1 589.1 546.8 Drawing amplification, N 9658 10956 9094 7547 5963 5044 3863 Drawing speed, m/min 120 124 159 198 253 319 398 Power consumed by electric drives, kWt 21.46 25.16 26.78 27.67 27.94 29.8 28.47 Electric energy consumption, kWt/h 143.56 Productivity, t/h 1.316 With a help of a mathematical model of temperature speed drawing mode on FIFO drawing mills wire temperature
Conclusion From this perspective to achieve drawing speeds stipulated by the drawing machine data sheet and increase stability of the drawing tool the approach to selecting the following process parameters on modern drawing machines must be changed: the single deformation (strain) degree and wire-die half-angle.
Online since: January 2010
Authors: Leo A.I. Kestens, Roumen H. Petrov, Orlando León-García
The fracture area of the broken specimens was
calculated by image analysis in order to obtain the reduction of area at fracture and the related true
stress.
The equipment employed for EBSD analysis was a NOVA600 Dual Beam scanning electron microscopy with field-emission gun and equipped with an OxfordHKL EBSD data collection system.
The main difference between both steels is the reduction of area at fracture where the slow cooled sample is characterized by a higher strain localization which is shown in Fig. 2c.
Quenched Slow cooled Tensile strength, [MPa] 723.4 ± 7.1 568 ± 3.8 Deformation at necking, [%] 13.39 ± 0.33 13.69 ± 0.18 Deformation at fracture, [%] 18.19 ± 0.61 17.59 ± 0.3 Reduction of area at fracture, [%] 49.7 ± 1.32 65.3 ± 0.89 True stress at fracture, [MPa] 1236.8 ± 27.4 1260.2 ± 13.9 Vickers microhardness, [VH] 214 ± 5.1 170 ± 4.1 Table 1 Mechanical properties of both DP steels obtained from tensile tests.
In summary, the quenched DP steel exhibits higher void activity than the slow cooled material but in both cases the void density is low and similar to data reported by Ahmad et al. [4].
The equipment employed for EBSD analysis was a NOVA600 Dual Beam scanning electron microscopy with field-emission gun and equipped with an OxfordHKL EBSD data collection system.
The main difference between both steels is the reduction of area at fracture where the slow cooled sample is characterized by a higher strain localization which is shown in Fig. 2c.
Quenched Slow cooled Tensile strength, [MPa] 723.4 ± 7.1 568 ± 3.8 Deformation at necking, [%] 13.39 ± 0.33 13.69 ± 0.18 Deformation at fracture, [%] 18.19 ± 0.61 17.59 ± 0.3 Reduction of area at fracture, [%] 49.7 ± 1.32 65.3 ± 0.89 True stress at fracture, [MPa] 1236.8 ± 27.4 1260.2 ± 13.9 Vickers microhardness, [VH] 214 ± 5.1 170 ± 4.1 Table 1 Mechanical properties of both DP steels obtained from tensile tests.
In summary, the quenched DP steel exhibits higher void activity than the slow cooled material but in both cases the void density is low and similar to data reported by Ahmad et al. [4].
Online since: May 2011
Authors: Xiao Ming Yuan, Rui Sun, Long Wei Chen
Incident of arbitry loading, ag(t), is a discrete data which can be read as,
, j=0, 1,2,3...
Modulus Reduction during Liquefaction Process.
The physical process of liquefaction is excess pore water pressure increases and results in shear modulus reduction.
The essential of liquefaction process is reduction of the subsoil modulus with increasing pore-water pressure.
Further verification for the reliability of the method proposed in this paper by laboratory testing and in-situ data needs more work.
Modulus Reduction during Liquefaction Process.
The physical process of liquefaction is excess pore water pressure increases and results in shear modulus reduction.
The essential of liquefaction process is reduction of the subsoil modulus with increasing pore-water pressure.
Further verification for the reliability of the method proposed in this paper by laboratory testing and in-situ data needs more work.
Online since: December 2012
Authors: Juan Li, Ning Li, Mei Xiu Li
The key in the reduction of special information by expansion is the design of information structure in actual conversion.
The numbering rules are not consistent with the source formats after round-trip conversion, and if the information is recorded to expansion directly and copied back to source format in reduction, it may cause identifier to conflict.
When OOXML is converted into UOF, the footer information is recorded in expansion; while UOF is converted into OOXML, this part of information should be extracted to realize the reduction of information.
When OOXML is converted into UOF, the slide content should ignore these pictures of which the placeholder are footer, number and data, and then call the conversion module in expansion.
The problem can be solved by adding corresponding steps to reduce the unnecessary data in pre-treatment and post-treatment.
The numbering rules are not consistent with the source formats after round-trip conversion, and if the information is recorded to expansion directly and copied back to source format in reduction, it may cause identifier to conflict.
When OOXML is converted into UOF, the footer information is recorded in expansion; while UOF is converted into OOXML, this part of information should be extracted to realize the reduction of information.
When OOXML is converted into UOF, the slide content should ignore these pictures of which the placeholder are footer, number and data, and then call the conversion module in expansion.
The problem can be solved by adding corresponding steps to reduce the unnecessary data in pre-treatment and post-treatment.
Online since: June 2008
Authors: Irena Topic, Heinz Werner Höppel, Matthias Göken
Ultrafine-grained materials show superior mechanical properties in terms of strength and
ductility compared to conventionally grained (CG) materials, which makes them especially
interesting for light weight construction in the automobile industry due the high specific strength
and the high potential for cost reduction [3, 4].
Originally developed by Thomas et al. [5, 6] in 1991, FSW has become a highly recognised joining technique due to numerous advantages, including higher weight reduction potential compared to standard mechanical fasteners, easier joining of the hard-to-weld materials such as Al alloys and a lower heat input compared to fusion welding [7, 8, 9, 10].
The surfaces were wire brushed to remove the oxide layer, stacked and rolled together without lubrication using a four high rolling mill (Carl Wezel, Mühlacker) to a 50 % thickness reduction.
Additional tests will be required to confirm the data.
At this stage, the microstructural observations and the bulge test data appear conflicting and the exact reasons for this behaviour are not yet clear.
Originally developed by Thomas et al. [5, 6] in 1991, FSW has become a highly recognised joining technique due to numerous advantages, including higher weight reduction potential compared to standard mechanical fasteners, easier joining of the hard-to-weld materials such as Al alloys and a lower heat input compared to fusion welding [7, 8, 9, 10].
The surfaces were wire brushed to remove the oxide layer, stacked and rolled together without lubrication using a four high rolling mill (Carl Wezel, Mühlacker) to a 50 % thickness reduction.
Additional tests will be required to confirm the data.
At this stage, the microstructural observations and the bulge test data appear conflicting and the exact reasons for this behaviour are not yet clear.
Online since: May 2012
Authors: Bo Yang, Qiang Liu, Ting Meng, Zhi Pei Zhang
According to the investigation data, the air-raid shelter’s size is a 4×3.2 m model.
The soil layer within the scope of the air-raid Shelter is made an assignment of physical and mechanical parameters, its main basis is the data provided by related engineering geological investigation reports, at the same time referring to Rock Mechanics Parameters Book and the Flac3d software’s principle of parameter and does some appropriate adjustment.
Because the site is planning to build a school, the stability of the shelter seriously affected the stability of the building and the personal safety of the staff, we must consider the reduction of the strength of lining structure on the shelter as time goes on, and the 75% intensity decreased in the engineering use period, the displacement and the stress conditions as below.
Shelter horizontal displacement equivalence value maps(mm) equivalence value maps(mm) The results of long-term stability analysis of the air-raid shelter shows that, time will lead to sharp reduction of the lining structure strength, the deformation of the vault and both sides continues to grow, the areas of damage increase further, the shelter will collapse, thus seriously affects the safe use.
The results of the long-term stability analysis about the site simulation of the shelter show that: time will lead to sharp reduction of the lining structure strength, the deformation of the vault and both sides of the shelter continues to increase and the damage scope increases.
The soil layer within the scope of the air-raid Shelter is made an assignment of physical and mechanical parameters, its main basis is the data provided by related engineering geological investigation reports, at the same time referring to Rock Mechanics Parameters Book and the Flac3d software’s principle of parameter and does some appropriate adjustment.
Because the site is planning to build a school, the stability of the shelter seriously affected the stability of the building and the personal safety of the staff, we must consider the reduction of the strength of lining structure on the shelter as time goes on, and the 75% intensity decreased in the engineering use period, the displacement and the stress conditions as below.
Shelter horizontal displacement equivalence value maps(mm) equivalence value maps(mm) The results of long-term stability analysis of the air-raid shelter shows that, time will lead to sharp reduction of the lining structure strength, the deformation of the vault and both sides continues to grow, the areas of damage increase further, the shelter will collapse, thus seriously affects the safe use.
The results of the long-term stability analysis about the site simulation of the shelter show that: time will lead to sharp reduction of the lining structure strength, the deformation of the vault and both sides of the shelter continues to increase and the damage scope increases.
Online since: March 2014
Authors: Xian Feng Li, Jian Guo Xu, Hao Zhang, Jun Dong, Yu Jie Pei
Due to the SCR as a regulator SVC execution unit, it has a continuous step less adjustment (by changing the thyristor conduction angle), especially suitable for some industrial applications that require fast compensation, such as metallurgy, petrochemical and other industrial load, can significantly improve the user's power factor (highest accessible 1), the greatest degree of energy loss reduction for users while reducing voltage fluctuations and flicker in public users connected to the grid points.
According to operational data, system uptime, the bus voltage changes are as follows: 220kV bus: Maximum: 231 kV Minimum: 226.4 kV; 66kV bus: Maximum: 70.5kV Min: 65.9 kV
According to the simulation and the actual test site, assuming normal TCR slip issued during the trip 40Mvar, system rated voltage is 66kV, the system failure, Wanghua Power Plant Unit 3 tripped splitting after TCR, FC slip road trip, will the system At least reactive voltage 2.5kV reduction (system voltage 63.5kV); and if TCR branch trip, FC slip reservations could only be caused by voltage 0.9kV reduction system (system voltage 65.1kV), fully meet the petrochemical other high-risk users of the supply voltage requirements.
SVC device into operation for Lishizhai network to improve power factor, stable voltage levels, reduce the power loss has played an integral role for the future into static reactive power compensation device SVC using accumulated valuable experience and data.
According to operational data, system uptime, the bus voltage changes are as follows: 220kV bus: Maximum: 231 kV Minimum: 226.4 kV; 66kV bus: Maximum: 70.5kV Min: 65.9 kV
According to the simulation and the actual test site, assuming normal TCR slip issued during the trip 40Mvar, system rated voltage is 66kV, the system failure, Wanghua Power Plant Unit 3 tripped splitting after TCR, FC slip road trip, will the system At least reactive voltage 2.5kV reduction (system voltage 63.5kV); and if TCR branch trip, FC slip reservations could only be caused by voltage 0.9kV reduction system (system voltage 65.1kV), fully meet the petrochemical other high-risk users of the supply voltage requirements.
SVC device into operation for Lishizhai network to improve power factor, stable voltage levels, reduce the power loss has played an integral role for the future into static reactive power compensation device SVC using accumulated valuable experience and data.
Online since: May 2014
Authors: J. Escudero, E. Solórzano, Miguel A. Rodríguez-Pérez, Javier Pinto, J. Martín de León, D. Velasco, B. Notario
Results of the amount of CO2 uptake as well as the final crystallinity for these materials are presented in Table 1 (data measured after 120 minutes of gas dissolution).
From CO2 uptake data (Table 1), it can be inferred that the peak appears when a threshold CO2 concentration (about 11-13 wt.%) is reached (time needed to reach this concentration decreases with the increment of pressure and increases with the increment of sample thickness as corresponds to gas dissolution processes).
It seems that the transmissivity evolution of PLA samples under CO2 pressure can be split into two or three phenomena contributing to the measured curves. 1) Reduction of transmissivity due to the crystallinity increment. 2) Reduction of transmissivity due to other phenomena related to the presence of CO2. 3) Small contribution of the CO2 sorption in the reduction of transmissivity.
From CO2 uptake data (Table 1), it can be inferred that the peak appears when a threshold CO2 concentration (about 11-13 wt.%) is reached (time needed to reach this concentration decreases with the increment of pressure and increases with the increment of sample thickness as corresponds to gas dissolution processes).
It seems that the transmissivity evolution of PLA samples under CO2 pressure can be split into two or three phenomena contributing to the measured curves. 1) Reduction of transmissivity due to the crystallinity increment. 2) Reduction of transmissivity due to other phenomena related to the presence of CO2. 3) Small contribution of the CO2 sorption in the reduction of transmissivity.
Online since: January 2015
Authors: Piotr Szota, Seweryn Wąsek, Andrzej Stefanik, Sebastian Mróz
This modification provides the possibility of increasing the bite angle, and thus applying larger reductions in rolling passes.
Also the stability of band plastic flow in the groove is improved, and a reduction in the non-uniformity of deformation over the bimetallic band width follows.
Each roll had an individual drive provided by a 7.5 kW rated-power asynchronous alternating-current motor via a reducer of a reduction ratio of 1:22.4 and a drive shaft.
This was due to, among other things, the employed method of measuring the cross-sectional areas of test samples, for which a Nikon Eclipse MA-200 optical microscope equipped with the NIS-Elements data acquisition and analysis software was used.
When examining the data shown in Figure 4 it can be noticed that the non-uniform distribution of copper layer thickness has been significantly minimized as compared with the results of studies [4, 5, 10–12].
Also the stability of band plastic flow in the groove is improved, and a reduction in the non-uniformity of deformation over the bimetallic band width follows.
Each roll had an individual drive provided by a 7.5 kW rated-power asynchronous alternating-current motor via a reducer of a reduction ratio of 1:22.4 and a drive shaft.
This was due to, among other things, the employed method of measuring the cross-sectional areas of test samples, for which a Nikon Eclipse MA-200 optical microscope equipped with the NIS-Elements data acquisition and analysis software was used.
When examining the data shown in Figure 4 it can be noticed that the non-uniform distribution of copper layer thickness has been significantly minimized as compared with the results of studies [4, 5, 10–12].
Online since: October 2015
Authors: Alexander P. Ilyin, Anton S. Brichkov, Anastasiya V. Zabolotskaya, Valentina V. Smirnova
Reduction of weight (wt.% by weight of the initial sample) sample of titanium dioxide and treated with ultrasonic probe in distilled water, depending on the heating temperature
Designation of the sample
Reducing the mass of the test samples (wt.% by weight of the initial sample) versus temperature heating
The total weight reduction, wt. %
The value endoeffect, J/g (t, °C)
20-200, °C
200-400, °C
400-600, °C
600-800, °C
800-1000, °C
< 60 °С
< 200 °С
S1
0.56
0.49
0.43
0.12
1.6
98.8 (44 °С)
124.4 (181 °С)
S2
0.45
0.27
0.40
0.18
1.3
104.1 (34 °С)
96.2 (184 °)
S3
0.64
0.75
0.24
0.17
1.8
93.0 (51 °С)
146.7 (180 °С)
Comparing the results of thermal analysis of samples of titanium dioxide was activated ultrasound and DC in deionised water (Tab. 1) and sample splitting TiO2 made in different parts of the interelectrode space, can make a conclusion (the results of the calculation of the total weight reduction samples) that, depending on what part of the interelectrode space was a sample formed on
The absorption maximum (and their intensities) in the IR spectra of the samples of titanium dioxide, and treated with ultrasonic probe in distilled water and taken in different parts of the interelectrode space Designation of the sample Identification S1 S2 S3 S (the samples annealed at 1000 °C) Maximum absorption bands (cm-1)intensity (%) 3734 – 9 3734 – 6 3730 – 10 ν (OH) 3465 – 26 3425 – 18 3472 – 28 3386 – 17 3318 – 27 3341 – 18 3318 – 29 3412 – 19 1626 – 15 1625 – 9 1635 – 18 – δ (H2O) 1467 – 13 1462 – 8 1426 – 17 – δ (≡Ti-O(H)-Ti≡) 1144 – 46 1136 – 32 1033 – 51 – δ (TiOH) 734 – 88 728 – 86 731 – 89 745 – 74 ν (TiO) 664 – 90 686 – 87 687 – 90 654 – 77 549 – 88 536 – 86 652 – 90 786 – 73 According to the data change ratio of a DC effect of various functional groups on the surface of the titanium dioxide on the location of the sample in the electrochemical cell are based.
The recovery rate (α,%) admixtures of iron ions, manganese ions, nickel ions and chloride ions after adsorption on titanium dioxide samples obtained by treatment in the ultrasonic probe and distilled water, and taken in different parts of the interelectrode space in comparison with non-treated TiO2 Designation of the sample TiO2 in H2O TiO2 without H2O TiO2 annealed at 1000 °C S1 S2 S3 S0 S α, % iron ions 65.9 64.4 70.2 38.7 18.6 manganese ions 74.2 70.3 75.0 42.8 21.4 nickel ions 59.7 57.3 63.5 40.5 20.2 chloride ions 61.5 63.7 59.1 43.3 15.7 According to the data presented in Table 3, the sample S0 was inferior in relation to the sorbent-soluble impurities metal cations and chloride ions.
The absorption maximum (and their intensities) in the IR spectra of the samples of titanium dioxide, and treated with ultrasonic probe in distilled water and taken in different parts of the interelectrode space Designation of the sample Identification S1 S2 S3 S (the samples annealed at 1000 °C) Maximum absorption bands (cm-1)intensity (%) 3734 – 9 3734 – 6 3730 – 10 ν (OH) 3465 – 26 3425 – 18 3472 – 28 3386 – 17 3318 – 27 3341 – 18 3318 – 29 3412 – 19 1626 – 15 1625 – 9 1635 – 18 – δ (H2O) 1467 – 13 1462 – 8 1426 – 17 – δ (≡Ti-O(H)-Ti≡) 1144 – 46 1136 – 32 1033 – 51 – δ (TiOH) 734 – 88 728 – 86 731 – 89 745 – 74 ν (TiO) 664 – 90 686 – 87 687 – 90 654 – 77 549 – 88 536 – 86 652 – 90 786 – 73 According to the data change ratio of a DC effect of various functional groups on the surface of the titanium dioxide on the location of the sample in the electrochemical cell are based.
The recovery rate (α,%) admixtures of iron ions, manganese ions, nickel ions and chloride ions after adsorption on titanium dioxide samples obtained by treatment in the ultrasonic probe and distilled water, and taken in different parts of the interelectrode space in comparison with non-treated TiO2 Designation of the sample TiO2 in H2O TiO2 without H2O TiO2 annealed at 1000 °C S1 S2 S3 S0 S α, % iron ions 65.9 64.4 70.2 38.7 18.6 manganese ions 74.2 70.3 75.0 42.8 21.4 nickel ions 59.7 57.3 63.5 40.5 20.2 chloride ions 61.5 63.7 59.1 43.3 15.7 According to the data presented in Table 3, the sample S0 was inferior in relation to the sorbent-soluble impurities metal cations and chloride ions.