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Online since: September 2014
Authors: Mohamad El Mehtedi, Stefano Spigarelli, Nicola Clemente, A.M.S. Hamouda, Farayi Musharavati, Mauro Daurù, Marcello Cabibbo
To obtain statistically reliable data,for each experimental condition, matrix of 8x8 (64) indents were carried out.
The contact depth, hc, can be estimated from the load-displacement data as (Eq. 2): hc=hmax-e(Pmax/S) (2) where hmax is the maximum indenter penetration depth at the peak load, Pmax, e is a tip dependent constant, Sis the material stiffness.
At the same time, the substrate recorded a significant hardness reduction starting from 973 K, and at 1173 K their hardness was as low as 3-4 GPa, which, compared to the room temperature value of 13 GPa, means a dramatic reduction of 70-78%.
Present results are in good agreement with some previously reported data on similar coatings [6,8,9,28-32].
Nix, A method for interpreting the data from depth-sensing indentation instrurnents, J.
The contact depth, hc, can be estimated from the load-displacement data as (Eq. 2): hc=hmax-e(Pmax/S) (2) where hmax is the maximum indenter penetration depth at the peak load, Pmax, e is a tip dependent constant, Sis the material stiffness.
At the same time, the substrate recorded a significant hardness reduction starting from 973 K, and at 1173 K their hardness was as low as 3-4 GPa, which, compared to the room temperature value of 13 GPa, means a dramatic reduction of 70-78%.
Present results are in good agreement with some previously reported data on similar coatings [6,8,9,28-32].
Nix, A method for interpreting the data from depth-sensing indentation instrurnents, J.
Online since: July 2018
Authors: V. Pozniakov, L. Markashova, Olena M. Berdnikova, T. Alekseienko, S. Zhdanov
It was based on experimental data, received by a quantitative fractography method.
However, it is 1.6 reduction of ψ index and KCV–40 in HAZ metal in comparison with Vw = 72 m/h.
At that, HAZ metal phase composition changes from bainite-martensite to martensite, grain structure has 1.4 time refinement at microhardness reduction on average by 8%.
Reduction of test temperature to Ttest = − 40°С results in the mixed type of failure with quasi-brittle component (Vf = 15…20%) in zone I and up to 30% in zone II.
Reduction of test temperature results in failure with quasi-brittle component in zone I (Table 2, Figure 4, a-c) and in zone II the nature of failure remains ductile with small pits of dP = 2…5 μm size and coarse ones dP = 20…60 μm (Figure 4, d-f).
However, it is 1.6 reduction of ψ index and KCV–40 in HAZ metal in comparison with Vw = 72 m/h.
At that, HAZ metal phase composition changes from bainite-martensite to martensite, grain structure has 1.4 time refinement at microhardness reduction on average by 8%.
Reduction of test temperature to Ttest = − 40°С results in the mixed type of failure with quasi-brittle component (Vf = 15…20%) in zone I and up to 30% in zone II.
Reduction of test temperature results in failure with quasi-brittle component in zone I (Table 2, Figure 4, a-c) and in zone II the nature of failure remains ductile with small pits of dP = 2…5 μm size and coarse ones dP = 20…60 μm (Figure 4, d-f).
Online since: February 2012
Authors: Reangroaj Roajanasiri, Nitin Afzulpurkar, Siridech Boonsang
Many cost reduction are done on product design, material cost and manufacturing operation.
The product performance will be considered to prevent the reduction of reliability and degradation.
This data is collected for a month.
Fig. 3: The Maximum temperature profiles for single laser pulse Fig. 4: The Maximum temperature profiles for 2 laser pulse (a) (b) Fig. 5: a:The pull test data of heat experiment, b: The bridging model validation Conclusion The simulation shows how model responds the laser pulse.
The product performance will be considered to prevent the reduction of reliability and degradation.
This data is collected for a month.
Fig. 3: The Maximum temperature profiles for single laser pulse Fig. 4: The Maximum temperature profiles for 2 laser pulse (a) (b) Fig. 5: a:The pull test data of heat experiment, b: The bridging model validation Conclusion The simulation shows how model responds the laser pulse.
Online since: May 2013
Authors: Morteza Rajab Zadeh, O.V. Ivchenko, V.A. Zaloga
Date accepted: 15 April 2013]
Keywords: Social accountability (responsibility), International standard SA 8000, Statistical data, Competitiveness of organizations, international market
Abstract.
Data obtained from the international organization SAAS (Social Accountability Accreditation Services) were analyzed using bar charts, percentages and Pareto (ABC) analysis.
Methodology This article is based on input data presented by the international organization SAAS (Social Accountability Accreditation Services) [11, 12, 13].
During the conducted research, the statistical and graphical methods of data processing and analysis, and Pareto or ABC analysis were used.
Table 1 shows the analysis of the statistical data which are displayed in Figure 2 and presented in the reference [6].
Data obtained from the international organization SAAS (Social Accountability Accreditation Services) were analyzed using bar charts, percentages and Pareto (ABC) analysis.
Methodology This article is based on input data presented by the international organization SAAS (Social Accountability Accreditation Services) [11, 12, 13].
During the conducted research, the statistical and graphical methods of data processing and analysis, and Pareto or ABC analysis were used.
Table 1 shows the analysis of the statistical data which are displayed in Figure 2 and presented in the reference [6].
Effect of Austenite Grain Size on the Mechanical Properties in Air-Cooled 0.1C-5Mn Martensitic Steel
Online since: May 2014
Authors: Shiro Torizuka, Toshihiro Hanamura, Soutaro Tamura, Shohei Enokida, Hiroshi Takech
aHANAMURA.Toshihiro=nims.go.jp, bTORIZUKA.Shiro=nims.go.jp
Keywords: high strength steel, total balance, reduction of area, uniform elongation, local elongation, true stress-true strain curve.
This data gives a good proof that cooling rate, 1K/sec, is stable down to room temperature even though there is a martensitic transformation starting around 340ºC.
However, when the size of the grain, within which the micro void exists, is small enough, the stress required for the micro void growth increases and then the crack progress is retarded, leading to the enhancement of the local strain and the reduction in area.
[1] As has been reported elsewhere, also in the low C-5Mn steel, Ms and Mf are found to decrease with decreasing the austenite grain size. [2] With the refinement of austenite grain size, the packet size and the block length decrease, while the lath width and the block width change only slightly, suggesting that the HV value for each specimen is almost the same. [3] A reduction in austenite grain size increases both fracture strength and fracture strain, showing a possibility of having excellent total balance properties Acknowledgement This study was supported by the Japan Science and Technology Agency under “Heterogeneous Structure Control,” a collaborative research initiative based on industrial demand.
This data gives a good proof that cooling rate, 1K/sec, is stable down to room temperature even though there is a martensitic transformation starting around 340ºC.
However, when the size of the grain, within which the micro void exists, is small enough, the stress required for the micro void growth increases and then the crack progress is retarded, leading to the enhancement of the local strain and the reduction in area.
[1] As has been reported elsewhere, also in the low C-5Mn steel, Ms and Mf are found to decrease with decreasing the austenite grain size. [2] With the refinement of austenite grain size, the packet size and the block length decrease, while the lath width and the block width change only slightly, suggesting that the HV value for each specimen is almost the same. [3] A reduction in austenite grain size increases both fracture strength and fracture strain, showing a possibility of having excellent total balance properties Acknowledgement This study was supported by the Japan Science and Technology Agency under “Heterogeneous Structure Control,” a collaborative research initiative based on industrial demand.
Online since: December 2010
Authors: Irina Kaganova, Alexey Reshetov, Viktor Varyukhin, Alexander Korshunov, A. Smolyakov, A. Morozov, Yan Beygelzimer
The value of the reduction in area remained at the initial value.
These undoubtedly important data make it possible to estimate the efficiency of the SPD processing, but do not show the distribution of mechanical properties across the billets.
As is known [7], this characteristic includes the uniform elongation and local elongation, which is characterized by the reduction in area ψ.
As can be seen from Table 2, the reduction in area remained at the same level.
The value of the reduction in area remained at the initial value.
These undoubtedly important data make it possible to estimate the efficiency of the SPD processing, but do not show the distribution of mechanical properties across the billets.
As is known [7], this characteristic includes the uniform elongation and local elongation, which is characterized by the reduction in area ψ.
As can be seen from Table 2, the reduction in area remained at the same level.
The value of the reduction in area remained at the initial value.
Online since: January 2010
Authors: Vladyslav N. Shyvanyuk, S. M. Teus, Valentin Gavriljuk
The analysis of the
electronic and elasticity approaches to HELP is carried out using the experimental data.
It follows from the estimation made in [7] that about 10 -2 of H/Me ratio is sufficient for the reduction of the repulsive force.
It was obtained (see Fig. 2) that hydrogen increases the density of electron states at the Fermi level, which is consistent with the experimental data.
Let us test these predictions using the experimental data for hydrogen, nitrogen and carbon in austenitic steels, where the elasticity theory does not predict any qualitative difference between interstitial atoms.
Thus, the presented experimental data can be explained based on the electronic approach to the HELP theory and cannot be interpreted in terms of the continuum mechanics.
It follows from the estimation made in [7] that about 10 -2 of H/Me ratio is sufficient for the reduction of the repulsive force.
It was obtained (see Fig. 2) that hydrogen increases the density of electron states at the Fermi level, which is consistent with the experimental data.
Let us test these predictions using the experimental data for hydrogen, nitrogen and carbon in austenitic steels, where the elasticity theory does not predict any qualitative difference between interstitial atoms.
Thus, the presented experimental data can be explained based on the electronic approach to the HELP theory and cannot be interpreted in terms of the continuum mechanics.
Online since: September 2013
Authors: Zhao Wei Shen, Cun Hong Pan, Sui Gao Ye, Hai Yan Lu, Li Hui Wang
Using regional economy, population, and geography data of 2008, the economic loss caused by dam failure was evaluated.
Using regional economy, population, and geography data as main input, it is then integrated with the dam-break flood routing model to acquire the hydraulic parameters, including depth, duration and velocity, and then to estimate the economic loss.
The first part is collection of geography, population and economic data of all these areas.
Since data, investigation, and reports from local government are mostly based on town, the estimation area is divided on the basis of town, too.
Using the above model and data, the direct loss is 1,655,360,000 RMB and the indirect loss is 413,840,000 RMB with the converting coefficient to be 25%, making the total value nearl 2,100 million RMB.
Using regional economy, population, and geography data as main input, it is then integrated with the dam-break flood routing model to acquire the hydraulic parameters, including depth, duration and velocity, and then to estimate the economic loss.
The first part is collection of geography, population and economic data of all these areas.
Since data, investigation, and reports from local government are mostly based on town, the estimation area is divided on the basis of town, too.
Using the above model and data, the direct loss is 1,655,360,000 RMB and the indirect loss is 413,840,000 RMB with the converting coefficient to be 25%, making the total value nearl 2,100 million RMB.
Online since: July 2022
Authors: Lorenzo Donati, Barbara Reggiani, Marco Negozio, Riccardo Pelaccia
The optimized designs showed temperature deviations below the 16 °C as well as the reduction of 50% in terms of nitrogen consuming.
The experimental data and the numerical simulations of the selected industrial case proved the cooling effectiveness of the original channel design but also the unbalance of the thermal gradient around the bearings and the non-optimal handling of nitrogen consuming, thus offering a suitable test case.
Therefore, only the main data are here synthetically recalled for the sake of clarity of the present work.
In terms of nitrogen consuming a reduction of about 60% was gain with both optimized designs.
The efficient investigation of the optimization design space allowed identifying and selecting solutions that led to a significant improvement of the cooling balancing around the bearings as well as to the reduction of the nitrogen consumption, obtaining temperature differences below 16°C in all selected configurations and the reduction of about 60% in terms of nitrogen flow rate.
The experimental data and the numerical simulations of the selected industrial case proved the cooling effectiveness of the original channel design but also the unbalance of the thermal gradient around the bearings and the non-optimal handling of nitrogen consuming, thus offering a suitable test case.
Therefore, only the main data are here synthetically recalled for the sake of clarity of the present work.
In terms of nitrogen consuming a reduction of about 60% was gain with both optimized designs.
The efficient investigation of the optimization design space allowed identifying and selecting solutions that led to a significant improvement of the cooling balancing around the bearings as well as to the reduction of the nitrogen consumption, obtaining temperature differences below 16°C in all selected configurations and the reduction of about 60% in terms of nitrogen flow rate.
Online since: September 2007
Authors: Niels Hansen
The analysis of the structural
data is based on the assumption that similar underlying mechanisms control the formation and
evolution of deformation microstructures.
This trend agrees well with experimental data.
The large amount of structural information which can be obtained by modern microscopical techniques requires organizing principles to facilitate the data analysis.
The many processes to produce nanostructured metals have resulted in a large variety of deformation microstructures but lack of reproducibility together with the inherent difficulty in the analysis of such fine structures has limited the amount of quantitative data.
In parallel to the increase in strength as the structural scale decreases a reduction in ductility is observed.
This trend agrees well with experimental data.
The large amount of structural information which can be obtained by modern microscopical techniques requires organizing principles to facilitate the data analysis.
The many processes to produce nanostructured metals have resulted in a large variety of deformation microstructures but lack of reproducibility together with the inherent difficulty in the analysis of such fine structures has limited the amount of quantitative data.
In parallel to the increase in strength as the structural scale decreases a reduction in ductility is observed.