Investigation of Spiking in Electron Beam Welding Using Stationary Stochastic Models

1977 ◽  
Vol 99 (2) ◽  
pp. 323-326 ◽  
Author(s):  
M. S. Phadke ◽  
A. M. Joglekar ◽  
S. M. Wu
Keyword(s):  
Electron Beam ◽  
Regression Models ◽  
Electron Beam Welding ◽  
Mechanistic Model ◽  
Beam Current ◽  
Heat Energy ◽  
Random Fluctuation ◽  
Beam Power ◽  
Model Parameters ◽  
Order Continuous

The spiking phenomenon in electron beam welding is characterized using the second-order continuous autoregressive model. The model parameters are then physically interpreted in terms of the random fluctuation in the beam power and the diffusion of heat energy in the plates being welded; and a mechanistic model is proposed for the spiking phenomenon. Finally, regression models are obtained to relate the spiking behavior to the accelerating voltage, the beam current, and the welding speed.

scholarly journals Metallurgical and Mechanical Research on Dissimilar Electron Beam Welding of AISI 316L and AISI 4340

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
A. R. Sufizadeh ◽  
S. A. A. Akbari Mousavi
Keyword(s):  
Electron Beam ◽  
Electron Beam Welding ◽  
Weld Zone ◽  
Tensile Tests ◽  
Beam Current ◽  
Aisi 316L ◽  
Cooling Rates ◽  
Minimum Width ◽  
Optimum Sample ◽  
Aisi 4340

Dissimilar electron beam welding of 316L austenitic stainless steel and AISI 4340 low alloy high strength steel has been studied. Studies are focused on effect of beam current on weld geometry, optical and scanning electron microscopy, X-ray diffraction of the weld microstructures, and heat affected zone. The results showed that the increase of beam current led to increasing depths and widths of the welds. The optimum beam current was 2.8 mA which shows full penetration with minimum width. The cooling rates were calculated for optimum sample by measuring secondary dendrite arm space and the results show that high cooling rates lead to austenitic microstructure. Moreover, the metallography result shows the columnar and equiaxed austenitic microstructures in weld zone. A comparison of HAZ widths depicts the wider HAZ in the 316L side. The tensile tests results showed that the optimum sample fractured from base metal in AISI 316L side with the UTS values is much greater than the other samples. Moreover, the fractography study presents the weld cross sections with dimples resembling ductile fracture. The hardness results showed that the increase of the beam current led to the formation of a wide softening zone as HAZ in AISI 4340 side.

Some Issues of Repairing Manned Space Vehicles in Outer Space Using Electron Beam Welding

2021 ◽  
Vol 315 ◽  
pp. 101-105
Author(s):  
Leonid M. Lobanov ◽  
E.A. Asnis ◽  
Ye.G. Ternovy ◽  
Yu.V. Zubchenko ◽  
I.I. Statkevich ◽  
...  
Keyword(s):  
Electron Beam ◽  
Open Space ◽  
Electron Beam Welding ◽  
Outer Space ◽  
Beam Power ◽  
Space Vehicles ◽  
Automatic Mode ◽  
Manned Space ◽  
Robotic Devices ◽  
New Generation

A new generation of electron beam tool for welding during assembly and repair-restoration works on board of manned space vehicles in open space was demonstrated. The tool includes a small-sized electron beam gun (EBG) with an electron beam power of up to 2.5 kW and a high-voltage power source with a voltage of 10 kV. The design of the electron-optical system of EBG allows using it in both manual as well as in automatic mode applying robotic devices. Applying the manufactured EBG and manipulator, in vacuum chamber the works on simulating the repair of a spacecraft’s section of aluminum 2219 alloy were carried out. The obtained results of studying the structure and mechanical characteristics and also sealing of welds confirmed the high quality of welded joints and a reliability of the technology for repairing a damaged fragment of a spacecraft's body using electron beam welding.

Study on Electron Beam Welding of AZ61 Magnesium Alloy

2010 ◽  
Vol 34-35 ◽  
pp. 1516-1520
Author(s):  
Hong Ye ◽  
Han Li Yang ◽  
Zhong Lin Yan
Keyword(s):  
Electron Beam ◽  
Magnesium Alloys ◽  
Welding Speed ◽  
Electron Beam Welding ◽  
Weld Zone ◽  
Welding Process ◽  
Processing Parameters ◽  
Beam Current ◽  
Fine Grained ◽  
Section Shape

Electron beam welding process of AZ61 with 10mm thickness magnesium alloys was investigated. The influence of processing parameters including focusing current, welding beam current and welding speed was researched. The results show that an ideal weld bead can be formed by choosing processing parameters properly. Focusing current is main parameter that determines cross section shape. The beam current and welding speed are main parameters that determine the weld width and dimensions. The test results for typical welds indicate that the microhardness of the weld zone is better than that of the base meta1. A fine-grained weld region has been observed and no obvious heat-affected zone is found. The fusion zone mainly consists of small α-Mg phase and β-Mg17A112. The small grains and β phases in the joint are believed to play an important role in the increase of the strength of weld for AZ61 magnesium alloys.

scholarly journals Динамическое управление мощностью мегаваттного электронного пучка субмиллисекудной длительности в источнике с плазменным катодом

2021 ◽  
Vol 47 (10) ◽  
pp. 38
Author(s):  
М.С. Воробьёв ◽  
П.В. Москвин ◽  
В.И. Шин ◽  
Н.Н. Коваль ◽  
К.Т. Ашурова ◽  
...  
Keyword(s):  
Electron Beam ◽  
Beam Energy ◽  
Maximum Rate ◽  
Control Method ◽  
Beam Current ◽  
Rate Of Change ◽  
Beam Power ◽  
Metallic Materials ◽  
Plasma Cathode ◽  
Variable Power

The paper describes a method for a controlled change in the power of an electron beam during a pulse of submillisecond duration, using a source "SOLO" with a plasma cathode. The beam power is controlled by changing the amplitude of the beam current with a corresponding change in the concentration of the emission plasma. This control method allows generating submillisecond beams of variable power (up to 10 MW at a maximum rate of change of no more than 0.5 MW/µs), which can be used for processing various metallic materials in order to change the functional properties of their surface with the ability to control the rate of input of beam energy into the surface of these materials.

scholarly journals Modeling And Prediction of Mechanical Strength in Electron Beam Welded Dissimilar Metal Joints of Stainless Steel 304 and Copper Using Grey Relation Analysis

2018 ◽  
Vol 7 (3.6) ◽  
pp. 198 ◽  
Author(s):  
R Ajith Raj ◽  
M Dev Anand
Keyword(s):  
Stainless Steel ◽  
Electron Beam ◽  
Electron Beam Welding ◽  
Pure Copper ◽  
Dissimilar Materials ◽  
Beam Current ◽  
Dissimilar Metal ◽  
Stainless Steel 304 ◽  
Input Parameters ◽  
Relation Analysis

Aircraft industries witness an extensive variety of utilizations in unique welded joints thinking about the benefit of quality and high corrosion protection. In any case, joining of dissimilar materials is more mind boggling because of the distinction in material properties. In this investigation dissimilar metal joints of pure Copper plates and Stainless Steel 304 plates of 3mm thickness were welded with Electron Beam Welding. The welding input parameters like Welding speed, Beam current and Work distance liable to quality of weld are considered. Plan of analysis has been made utilizing Taguchi strategy with three levels of input values. Ultimate tensile strength and hardness number were found to decide the mechanical quality. Both the yield esteems are consolidated for expectation and optimized using Gray Relation Analysis (GRA). The impacts of the input parameters towards weld quality were analyzed using ANOVA. 

Effect on LY12 Aluminum Alloy Welding Joint Microstructure and Properties with Electron Beam Welding Technical Parameters

2013 ◽  
Vol 475-476 ◽  
pp. 1275-1279
Author(s):  
Qiang Zheng ◽  
Cheng Gang Yang ◽  
Yu He ◽  
He Chen ◽  
Ai Wu Yu
Keyword(s):  
Aluminum Alloy ◽  
Electron Beam ◽  
Weld Metal ◽  
Heat Affected Zone ◽  
Welding Speed ◽  
Electron Beam Welding ◽  
Beam Current ◽  
Electron Beam Current ◽  
Micro Hardness ◽  
Technical Parameters

LY12 aluminum alloy was welded with vacuum electron beam welding, the effect of welding speed and electron beam current on the weld microstructure and mechanical properties of welding joints were studied, the results were shown that with the increasing of welding speed or decreasing of electron beam current, the grains in weld metal were refined, so the joint strength were increased. When the electron beam current was 18mA, the welding speed was 1000mm/min, the grains of weld metal were the finest, and the tensile strength was 373.2MPa. In addition, the micro-hardness of weld metal was much lower than base metal and heat affected zone, and the heat affected zone had certain softening phenomenon. With the increasing of welding speed or decreasing of electron beam current, the micro-hardness of weld metal was increased respectively.

Heat source model for electron beam welding of nickel-based superalloys

2021 ◽  
Vol 63 (1) ◽  
pp. 17-28
Author(s):  
Torsten Jokisch ◽  
Nikolay Doynov ◽  
Ralf Ossenbrink ◽  
Vesselin Georgiev Michailov
Keyword(s):  
Electron Beam ◽  
Heat Source ◽  
Electron Beam Welding ◽  
Experimental Studies ◽  
Theoretical Models ◽  
Source Model ◽  
Beam Deflection ◽  
Prediction Algorithm ◽  
Model Parameters ◽  
Heat Source Model

Abstract An adapted heat source model is developed for transient thermal numerical analysis of electron beam welded nickel-based alloy with increased susceptibility to hot cracking. The model enables the consideration of heat redistribution due to beam deflection phenomena. The modeling concept is validated by the appropriate theoretical models and in addition, experimental studies especially performed for this purpose. Special attention is given to the calibration of heat source model parameters. The calibration procedure is based on a statistical approach involving a combination of novel analytical solutions and quasi-steady state finite element models. The model parameter field is statistically analyzed, and a prediction algorithm is developed using optimization algorithms from the six sigma theory. The reliability and practicability of the model is demonstrated by validation weldments. The work is dedicated to precisely calculating the temperature field in the high temperature region around the weld pool and thus to provide a more detailed explanation of the formation of hot cracks when welding turbine materials commonly used in industry and aircraft constructions.

Electron beam welding with programming of beam power density distribution

2020 ◽  
Vol 2020 (1) ◽  
pp. 49-53
Author(s):  
V.V. Skryabinskyi ◽  
◽  
V.M. Nesterenkov ◽  
M.O. Rusynyk ◽  
◽  
...  
Keyword(s):  
Electron Beam ◽  
Density Distribution ◽  
Power Density ◽  
Electron Beam Welding ◽  
Beam Power ◽  
Power Density Distribution
Sign in / Sign up

Export Citation Format

Share Document