Effect of EBW Parameters on Weldment Quality of Ti6Al4V Alloy

2015 ◽  
Vol 830-831 ◽  
pp. 249-252
Author(s):  
M. Gopalakrishna Pillai ◽  
P.S. Sreejith ◽  
R.K. Gupta ◽  
Bhanu Pant ◽  
P.C. Harikumar ◽  
...  
Keyword(s):  
Anode Voltage ◽  
Beam Current ◽  
Main Beam ◽  
Weld Penetration ◽  
Eb Welding ◽  
Depth Of Penetration ◽  
Distance Constant ◽  
Influencing Parameters ◽  
Maximum Penetration

The penetration characteristics of EBW are primarily dependent on the main beam current (Iw), potential difference between the cathode and anode (voltage, V) and the welding speed (S). There are other influencing parameters like weld focus current (If), welding gun to work distance (GW) and beam oscillation.In the present study, the effect of work distance on focus current and on penetration of Ti6Al4V weld is studied using a 60kV, 30kW EB welding machine. Weld focus current is measured over a range of work distance and variation in its pattern is studied. Similarly, the variation of depth of penetration by varying the work distance and varying the focus current at a particular work distance constant are also analyzed.It is observed that, focus current is inversely proportional to the work distance and the variation in focus current per unit change of work distance is high in the shorter work distance region. The change in focus current and work distance affects the weld penetration and fusion zone geometry. For optimum penetration at a given work distance, the beam focus should be below the surface in keyhole welding. As the work distance increases, the penetration capacity of the beam decreases and maximum penetration is obtained in lesser work distance region.

The Determination and Application of the Point Spread Function in the Scanning Electron Microscope

2018 ◽  
Vol 24 (4) ◽  
pp. 396-405 ◽  
Author(s):  
Matthew D. Zotta ◽  
Mandy C. Nevins ◽  
Richard K. Hailstone ◽  
Eric Lifshin
Keyword(s):  
Spatial Distribution ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Beam Current ◽  
Beam Shape ◽  
Practical Applications ◽  
Energy Beam ◽  
Working Distance ◽  
Scanning Electron

AbstractA method is presented to determine the spatial distribution of electrons in the focused beam of a scanning electron microscope (SEM). Knowledge of the electron distribution is valuable for characterizing and monitoring SEM performance, as well as for modeling and simulation in computational scanning electron microscopy. Specifically, it can be used to characterize astigmatism as well as study the relationship between beam energy, beam current, working distance, and beam shape and size. In addition, knowledge of the distribution of electrons in the beam can be utilized with deconvolution methods to improve the resolution and quality of backscattered, secondary, and transmitted electron images obtained with thermionic, FEG, or Schottky source instruments. The proposed method represents an improvement over previous methods for determining the spatial distribution of electrons in an SEM beam. Several practical applications are presented.

Comparison of Standardized Test Methods for Determining the Permeability of the Surface Layer of Concrete

2015 ◽  
Vol 1122 ◽  
pp. 141-144
Author(s):  
Tereza Komárková ◽  
Monika Králíková ◽  
Dalibor Kocáb ◽  
Petr Misák ◽  
Tomáš Stavař
Keyword(s):  
Surface Layer ◽  
Water Permeability ◽  
Standardized Test ◽  
Test Methods ◽  
Standardized Assessment ◽  
Depth Of Penetration ◽  
The Individual ◽  
Durability Of Concrete

The durability of concrete can be assessed based on the quality of the surface layer of concrete, for which there are a few standardized assessment test methods. Usually, the quality of the surface layer of concrete is evaluated based on its air and water permeability. The aim of this experiment was to compare the outputs which provide some methods for determining the permeability of the surface layer of concrete (GWT, ISAT, TPT, the depth of penetration of water under pressure). The measured values using the individual methods of assessing the permeability of the surface layer of concrete very closely correspond.

scholarly journals Plane wave ultrasound imaging using synthetic aperture image reconstruction techniques

2021 ◽  
Author(s):  
Dae-Myoung (Danny) Yang
Keyword(s):  
Image Reconstruction ◽  
Image Quality ◽  
Plane Wave ◽  
Ultrasound Imaging ◽  
Plane Waves ◽  
Reconstruction Algorithm ◽  
Synthetic Aperture ◽  
Depth Of Penetration ◽  
Image Reconstruction Techniques

Ultrasound imaging based on transmitting plane waves (PW) enables ultrafast imaging. Coherent PW compounding ultrasound imaging can reach the image quality of optimal multifocus image. In the image reconstruction, it was assumed that an infinite extent PWs was emitted. In this thesis, we propose a new image reconstruction algorithm – Synthetic-aperture plane-wave (SAPW) imaging – without using this assumption. The SAPW imaging was compared with the PWs imaging in numerical simulations and experimental measurements. The measured RF data in PW imaging was first decoded in the frequency domain using a pseudoinverse algorithm to estimate the RF data Then, SAPW RF data were used to reconstruct images through the standard synthetic transit aperture (STA) method. Main improvements in the image quality of the SAPW imaging in comparison with the PWs imaging are increases in the depth of penetration and the field of view when contrast-to-noise ratio (CNR) was used as a quantitative metric.

scholarly journals Hospitaalbouw in Zimbabwe

Afrika Focus ◽  
1987 ◽  
Vol 3 (1-2) ◽  
pp. 81-105
Author(s):  
Wim Schuerman
Keyword(s):  
Health Care ◽  
Developing Countries ◽  
Care Facility ◽  
Health Care Facility ◽  
Human Values ◽  
Valid Conclusion ◽  
Functional Organisation ◽  
Influencing Parameters ◽  
To Come

Designing a hospital means making a study of all the influencing parameters of the form and functional organisation. The thoroughness of this process will determine the quality of the design itself. This article containes a distilation of such a process. By making such a study I hoped to come to a valid conclusion design different from the health – factories that are normally implanted in developing countries. This, by taking in account not only the health care facility on itself -with which we are quite familiar – but also the specific human values of the indegenious population.

Utilization of Process Monitoring in Ti Alloy Welding

2007 ◽  
Author(s):  
Z. Sun ◽  
D. Pan
Keyword(s):  
Process Monitoring ◽  
Welding Current ◽  
Clear Correlation ◽  
Ti Alloy ◽  
Weld Penetration ◽  
Bead Width ◽  
Activating Flux ◽  
Industrial Sectors ◽  
Critical Issues

Titanium alloys have found increased applications in various industrial sectors. One of the critical issues in quality control is the weld penetration during welding. In the present paper, tungsten inert gas (TIG) welding was used to weld 8.0-mm thick Ti-6Al-4V alloy plates with and without an activating flux. The effect of the activating flux on Ti alloy welding was investigated. A data acquisition system was used to monitor the welding current and voltage signals during welding. These signals were then correlated to the weld penetration information. Results show that by applying the activating flux on the Ti-6Al-4V alloy surface, weld penetration depth increases, while the corresponding weld bead width is reduced. It was also found that various welding conditions, particularly flux thickness, influence the effectiveness of the activating flux. Results from monitoring of the welding current and voltage signals reveal that there is a clear correlation between the signals and the weld penetration. By analyzing the acquired signals, inconsistency in weld penetration can be identified. This demonstrates that process monitoring can provide an effective way to assess the consistency of the weld penetration and thus the quality of the welds.

The Design of Computer Integrated Control System for Electron Beam Welder

2013 ◽  
Vol 380-384 ◽  
pp. 274-277 ◽  
Author(s):  
Han Min Ye ◽  
Xiao Fei Liu
Keyword(s):  
Electron Beam ◽  
Control System ◽  
Integrated Control ◽  
Welding Process ◽  
Beam Current ◽  
Electron Beam Current ◽  
Control Technology ◽  
Computer Communication ◽  
Plc Control

Based on computer and PLC control technology, the control system for electron beam welder has been studied in this paper. By using PLC control technology to implement the intelligent control (IC) in welding process and adopting the high-frequency inverter technology, to realize the high-voltage interlock protection, the quality of electron beam current spot as well as the welding technology has been improved. Concerning the requirements on the technical and process, the design of computer communication and PLC application software demonstrate the feasibility of this method.

Optimal Design of Bogie Parameters Determination Test Bench Gantry Framework Based on SolidWorks/Simulation

2011 ◽  
Vol 199-200 ◽  
pp. 1253-1256
Author(s):  
Dong Lin Zhang ◽  
Jian Su ◽  
Xiao Ning Cao ◽  
Hai Bin Gong
Keyword(s):  
Optimization Design ◽  
Test Bench ◽  
Mathematic Model ◽  
Simulation Software ◽  
Main Beam ◽  
Manufacturing Cost ◽  
Test Bed ◽  
Analysis And Design ◽  
Design And Manufacturing

On the basis of SolidWorks/Simulation FEA module, statics analysis and design optimization for bogie parameters determination test bench gantry framework are researched in this paper. Taking the optimization design of gantry framework main beam for example, an optimal mathematic model is established, the optimization goal is to reduce the quality of the main beam, and the constraints are displacement and stress. Simultaneously, the model is simulated by the SolidWorks/Simulation software. Compared with the initial design, the results show that the quality of main beam is reduced by 12.69%, the quality optimization goal of the gantry framework test bed is realized. Meanwhile, it not only reduced the design and manufacturing cost, but also enhanced the design efficiency.

scholarly journals The Imperfect Phase Pattern of Real Parabolic Radar Antenna and Data Quality

2016 ◽  
Vol 33 (12) ◽  
pp. 2655-2661 ◽  
Author(s):  
Ya-Chien Feng ◽  
Frédéric Fabry
Keyword(s):  
High Resolution ◽  
Data Quality ◽  
Radar Data ◽  
Main Beam ◽  
Phase Pattern ◽  
Ground Target ◽  
Antenna Phase ◽  
Phase Variations ◽  
Radar Antenna

AbstractAlthough antennas have well-known power patterns that are commonly used to understand the quality of measurements, they also have phase patterns that are difficult to obtain and are seldom discussed in the radar meteorological community. This study presents the characteristics of the antenna phase pattern of the McGill S-band radar. Phase variations in azimuth and elevation with respect to the main beam axis are obtained using high-resolution scans of an isolated ground target and of an emission source. The two-way phase pattern is relatively constant within the radar main beam, but it changes rapidly at the power minima between the main beam and the first sidelobe. The effects of this phase pattern on ground and weather targets were evaluated and were found to be much more pronounced for point targets than for distributed targets. Nevertheless, proper knowledge of the phase pattern of the radar antenna would enhance the ability to better select ground targets for radar refractivity retrieval and to estimate the quality of radar data.

scholarly journals Plane wave ultrasound imaging using synthetic aperture image reconstruction techniques

2021 ◽  
Author(s):  
Dae-Myoung (Danny) Yang
Keyword(s):  
Image Reconstruction ◽  
Image Quality ◽  
Plane Wave ◽  
Ultrasound Imaging ◽  
Plane Waves ◽  
Reconstruction Algorithm ◽  
Synthetic Aperture ◽  
Depth Of Penetration ◽  
Image Reconstruction Techniques

Ultrasound imaging based on transmitting plane waves (PW) enables ultrafast imaging. Coherent PW compounding ultrasound imaging can reach the image quality of optimal multifocus image. In the image reconstruction, it was assumed that an infinite extent PWs was emitted. In this thesis, we propose a new image reconstruction algorithm – Synthetic-aperture plane-wave (SAPW) imaging – without using this assumption. The SAPW imaging was compared with the PWs imaging in numerical simulations and experimental measurements. The measured RF data in PW imaging was first decoded in the frequency domain using a pseudoinverse algorithm to estimate the RF data Then, SAPW RF data were used to reconstruct images through the standard synthetic transit aperture (STA) method. Main improvements in the image quality of the SAPW imaging in comparison with the PWs imaging are increases in the depth of penetration and the field of view when contrast-to-noise ratio (CNR) was used as a quantitative metric.

scholarly journals Development of a simple, portable, colorimetric arsenic sensor based on Molybdenum Blue Chemistry

2021 ◽  
Author(s):  
Nevetha Yogarajah
Keyword(s):  
Image Reconstruction ◽  
Image Quality ◽  
Ultrasound Imaging ◽  
Plane Waves ◽  
Reconstruction Algorithm ◽  
Depth Of Penetration ◽  
Molybdenum Blue ◽  
Ultrafast Imaging ◽  
Infinite Extent

Ultrasound imaging based on transmitting plane waves (PW) enables ultrafast imaging. Coherent PW compounding ultrasound imaging can reach the image quality of optimal multifocus image. In the image reconstruction, it was assumed that an infinite extent PWs was emitted. In this thesis, we propose a new image reconstruction algorithm – Synthetic-aperture plane-wave (SAPW) imaging – without using this assumption. The SAPW imaging was compared with the PWs imaging in numerical simulations and experimental measurements. The measured RF data in PW imaging was first decoded in the frequency domain using a pseudoinverse algorithm to estimate the RF data Then, SAPW RF data were used to reconstruct images through the standard synthetic transit aperture (STA) method. Main improvements in the image quality of the SAPW imaging in comparison with the PWs imaging are increases in the depth of penetration and the field of view when contrast-to-noise ratio (CNR) was used as a quantitative metric

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