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Tytuł:
Numerical modelling of thermal phenomena in laser beam and hybrid welding processes using Abaqus FEA
Modelowanie numeryczne zjawisk cieplnych w procesie spawania laserowego i hybrydowego z wykorzystaniem Abaqus FEA
Autorzy:
Piekarska, W.
Kubiak, M.
Saternus, Z.
Powiązania:
https://bibliotekanauki.pl/articles/382721.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
laser beam welding
hybrid welding
temperature field
finite element analysis
spawanie laserowe
spawanie hybrydowe
pole temperatury
analiza elementów skończonych
Opis:
This paper concerns numerical analysis of thermal phenomena accompanying laser beam and laser-arc hybrid welding processes. Temperature field was obtained on the basis of the solution into energy conservation equation with Fourier law using finite element method. ABAQUS/Standard solver was used for calculations. Electric arc and laser beam heat sources were described respectively by “double ellipsoidal” heat source and Gaussian distribution with assumption of linear decrease of heat source power intensity with material penetration deep. Heat source movement along welded plate was obtained using DFLUX subroutine. Thermo-physical parameters dependant on temperature as well as latent heat of fusion were taken into account in FE analysis. The results of calculations include temperature field in rectangular elements butt welded by a single laser beam and hybrid laser-arc technique.
Praca dotyczy analizy numerycznej zjawisk cieplnych towarzyszących procesom spawania wiązką laserową oraz spawania hybrydowego laser-łuk elektryczny. Rozkłady temperatury otrzymano z numerycznego rozwiązania równania zachowania energii z prawem Fouriera metodą elementów skończonych. Do obliczeń wykorzystano moduł obliczeniowy ABAQUS/Standard. Do opisu rozkładu mocy łuku elektrycznego wykorzystano model „podwójnie elipsoidalny”, natomiast rozkład mocy wiązki laserowej opisano modelem gaussowskim z uwzględnieniem liniowego spadku intensywności mocy źródła z głębokością penetracji materiału. Symulację ruchu źródła spawającego uzyskano dzięki zastosowaniu procedury DFLUX. W analizie uwzględniono zmienne z temperaturą własności termofizyczne a także ciepło krzepnięcia w obszarze dwufazowym. Wyniki obliczeń numerycznych obejmują rozkłady temperatury w elementach prostopadłościennych spawanych doczołowo wiązką laserową i techniką hybrydową laser-łuk elektryczny.
Źródło:
Archives of Foundry Engineering; 2011, 11, 2 spec.; 185-190
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Repair Welding of the Massive Cast
Autorzy:
Bęczkowski, R.
Powiązania:
https://bibliotekanauki.pl/articles/381046.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
cast defect
rebuilding
quality
MAG
welding
wady odlewów
przebudowa
jakość
spawanie
Opis:
The rebuilding technologies are used to develop surface of ladle. Among many welding methods currently used to obtain surface layer without defects one of the most effective way of rebuilding is using metal arc welding. This additional material gives more possibilities to make expected quality of rebuild surface. Chemical composition, property and economic factors allow to use metal wire. Because of these reasons, solid wire gives opportunity to be wildly used as material to rebuild or repair the surface in different sectors of industry. The paper shows a few ways to rebuild the surface in the massive cast with the use of metal active gas welding for repair. The work presents studies of defect in the massive cast. It contains the pictures of microstructures and defects. The method of removing defects and the results of checking by visual and penetrant testing methods are shown. The papers describes the methodology of repair the ladle with metal active gas welding, preheating process and standards non destructive testing method.
Źródło:
Archives of Foundry Engineering; 2017, 17, 2; 5-8
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Arc welding renovation of permanent steel molds
Autorzy:
Šutka, Jozef
Koňar, R.
Moravec, J.
Petričko, L.
Powiązania:
https://bibliotekanauki.pl/articles/1837722.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
casting mould
renovation
welding
hardfacing
tribological test
formy odlewnicze
renowacja
spawanie
napawanie
Opis:
The paper deals with the possibility of the renovation of permanent steel molds for casting using electric arc welding technology. When casting liquid metal into permanent steel molds, there is chemical-thermo-mechanical wear of the surface of the mold cavity and the inlet system, which causes a deterioration of the surface quality and dimensional accuracy of the casting. For this reason, it is necessary to renovate the steel mold after a certain casting interval - mold life. In this case, the technology of manual electric arc welding with a coated electrode was used for the renovation. The welding renovation aims to increase the service life of the mold using carbide hardfacing welds, which after welding achieve high mechanical properties of the renovated mold parts. Two types of hardfacing coated electrodes were used for welding, namely the OK Weartrode 55HD electrode and the OK Weartrode 50T electrode. Macroscopic analysis, tribological tests as well as the measurement of the hardness of the welded layers were performed to evaluate the quality and the friction coefficients of the additional materials used. The properties of hardfacing welds were compared with the properties of the basic material of the high-alloy steel mold. The main advantage is in addition to increasing the durability and longevity of the mold, also reducing the cost of mold renovation compared to other renovation technologies.
Źródło:
Archives of Foundry Engineering; 2021, 21, 2; 35-40
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of the Content of δ Ferrite in Pulse-Arc Welded Steel 304
Autorzy:
Gucwa, M.
Bęczkowski, R.
Grzyb, A.
Powiązania:
https://bibliotekanauki.pl/articles/380266.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
stainless steel
ferrite
welding arc
Schaeffler diagram
stal nierdzewna
ferryt
spawanie
diagram Schaefflera
Opis:
The paper presents the results of research on the effect of the welding arc type on the content of δ ferrite, in the welded joint of 304 grade stainless steel. Based on the commonly used Schaefler diagram, the content of δ ferrite in the welded joint was estimated, and then these results were verified by comparing them with results obtained on specimens welded by different welding arc types, including the pulse arc. The obtained investigation results indicate some discrepancies between calculations made by analytical methods and the fraction of δ ferrite measured on the prepared specimens.
Źródło:
Archives of Foundry Engineering; 2014, 14, 1 spec.; 131-134
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical modeling of the welding phenomenon in forward aluminium extrusion process
Autorzy:
Piwnik, J.
Kuprianowicz, J.
Mogielnicki, K.
Powiązania:
https://bibliotekanauki.pl/articles/379472.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
plastic treatment
extrusion process
welding
tool design
obróbka plastyczna
proces wyciskania
spawanie
projektowanie narzędzi
Opis:
There is often need to use welding methods in the aluminium alloys extrusion processes. Welding methods while extruding are divided in to transverse and longitudinal one. In paper the energy criterions for transverse and longitudinal joining during extrusion of aluminium alloys in warm conditions are showed. Numerical simulation results for two cylindrical billets transverse joining, during forward extruding with using the flat punch are presented. Irregularity in the billets material flow and presence of a void are proved. In order to equalization the flowing billets volumes streams, the numerical model for forward extrusion of cylindrical billets, with using the punch with a toe and initially formed upper billet is proposed. The application of this method causes both transverse and longitudinal welding schemes appearing. Combination of two welding schemas gives the product, which has a core made of material from the upper billet and external layers of the lower billet.
Źródło:
Archives of Foundry Engineering; 2011, 11, 2 spec.; 191-194
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Resistance Welding of High-Manganese Cast Steel with Unalloyed Steel Rails
Autorzy:
Tasak, E.
Ziewiec, A.
Tuz, L.
Powiązania:
https://bibliotekanauki.pl/articles/380090.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
crossovers welding
hadfield cast steel
austenite spacer
dissimilar metals welding
zwrotnica
spawanie
staliwo
austenit
Opis:
The paper presents the influence of resistance welding parameters on the mechanical properties and structure of joints of the unalloyed steel rail and high-manganese crossover. As the spacer Cr-Ni austenitic cast steel with decreased austenite stability was used. The results show, that the austenitic cast steel with metastable structure of austenite provide to high strain hardening of spacer deformation during operation. The high increase of hardness is the result dislocation hardening and the transition of austenite into martensite. The content of ferrite &delta and martensite was measured by metallographic method and verified by X-ray diffraction phase analysis. Moreover, it was shown that to high welding parameters causes the cracks in HAZ of manganese iron cast and in the spacer near to fusion line with unalloyed cast steel. The reparation of cracks can be made by welding methods.
Źródło:
Archives of Foundry Engineering; 2014, 14, 1 spec.; 115-120
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Effect of Type of Welding Sequence During Hardfacing Chromium Cast Iron for Erosion Resistance
Autorzy:
Gucwa, M.
Bęczkowski, R.
Winczek, J.
Wyleciał, T.
Powiązania:
https://bibliotekanauki.pl/articles/382472.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
wear resistant alloys
hardfacing
erosion
welding
hardness
stopy odporne na zużycie
napawanie
erozja
spawanie
twardość
Opis:
The paper presents the capabilities of welding techniques to creating properties of wear resistant high chromium cast iron alloy. The use of the right kind of welding sequence allows you to change the structure and properties of the obtained welds. Tests were conducted for one type of additive material in the form of self shielded core wire. In order to determine the effect of the type of welding sequence on the properties of welds performed welding using string bead and weave bead. The resulting weld was tested on hardness and research structure in an optical microscope. In the following studies have been made erosive tests wear of made hardfacing. String beads gave structure rich in carbides and harder about 270 HV of the weld with weave bead. Also, wear resistance was nearly twice as better for welds made with string beads. In the experiment a decisive role in the resistance to wear plays a high hardness of the deposit and the presence of carbides in its structure. Changes in the basic parameters of the deposition process allows for the formation of structure and properties of hardfacing welds in a wide range.
Źródło:
Archives of Foundry Engineering; 2017, 17, 3; 51-54
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical modelling of liquid material flow in the fusion zone of hybrid welded joint
Modelowanie numeryczne ruchu ciekłego materiału w strefie przetopienia złącza spawanego hybrydowo
Autorzy:
Kubiak, M.
Powiązania:
https://bibliotekanauki.pl/articles/379665.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
solidification process
hybrid welding
fluid flow
numerical modelling
proces krzepnięcia
spawanie hybrydowe
przepływ cieczy
modelowanie numeryczne
Opis:
This paper concerns modelling of liquid metal motion in the fusion zone of laser-arc hybrid butt-welded plate. Velocity field in the fusion zone and temperature field in welded plate were obtained on the basis of the solution of mass, momentum and energy conservations equations. Differential equations were solved using Chorin’s projection method and finite volume method. Melting and solidification processes were taken into account in calculations assuming fuzzy solidification front where fluid flow is treated as a flow through porous medium. Double-ellipsoidal heat source model was used to describe electric arc and laser beam heat sources. On the basis of developed solution algorithms simulation of hybrid welding process was performed and the influence of liquid metal motion in the fusion zone on the results of calculations was analyzed.
Praca dotyczy modelowania ruchu ciekłego metalu w strefie przetopienia złącza spawanego doczołowo techniką hybrydową laser-łuk elektryczny. Pole prędkości w strefie przetopienia i pole temperatury w spawanym płaskowniku otrzymano z rozwiązania równań zachowania masy, pędu i energii. Do rozwiązania równań różniczkowych wykorzystano projekcję Chorina i metodę objętości skończonych. W obliczeniach uwzględniono procesy topienia i krzepnięcia złącza z założeniem rozmytego frontu krzepnięcia gdzie ruch cieczy traktowano jako przepływ przez medium porowate. Do opisu rozkładu mocy łuku elektrycznego i wiązki laserowej wykorzystano „podwójnie elipsoidalny” model źródła ciepła. Na podstawie opracowanych algorytmów przeprowadzono symulację procesu spawania hybrydowego analizując wpływ ruchu ciekłego metalu w strefie przetopienia na wyniki obliczeń.
Źródło:
Archives of Foundry Engineering; 2011, 11, 2 spec.; 117-123
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Influence of Lamellar Graphite Cast Iron Annealing on Hardness and Structure
Autorzy:
Roučka, J.
Prochazka, J.
Kana, V.
Krutis, V.
Nedelova, K.
Powiązania:
https://bibliotekanauki.pl/articles/380964.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
cast iron
welding
annealing
cast iron hardness
structure stability
żeliwo
spawanie
wyżarzanie
twardość żeliwa
struktura
stabilność
Opis:
An analysis has been carried out of the influence of annealing time at the preheating temperature of 650 °C on the change in hardness and alloy structure of lamellar graphite cast iron in the working as well as in the laboratory conditions. This preheat temperature is common during reclaiming welding of castings with complex shapes. The changes in unalloyed cast iron EN-GJL 200 to EN-GJL 300 according to ISO 1690 standard and cast iron with low amount of elements such as Sn, Cu, Cr, and Mo and their combinations were assessed. It was found that the cast iron of higher strength grades has better hardness and structural stability. Cast iron alloyed with chromium or its combinations has the highest stability. In unalloyed cast iron, a partial degradation of pearlite occurs; in alloyed cast iron the structural changes are not conclusive.
Źródło:
Archives of Foundry Engineering; 2019, 4; 105-112
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Repair of Foundry Defects in Steel Castings Using Welding Technology
Autorzy:
Mičian, M.
Koňár, R.
Hlavatý, I.
Winczek, J.
Gucwa, M.
Powiązania:
https://bibliotekanauki.pl/articles/380199.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
steel casting
repair by welding
mechanical testing
approval of welding procedure
odlew staliwny
spawanie naprawcze
badania mechaniczne
Opis:
Use of welding technology for the repair of steel castings is particularly common in two areas. These include weld surfacing of protrusions that remained incomplete after casting, or filling the surface defects (cavities). These defects are more common for steel casting than for graphite cast iron, due to the lower fluidity of steel. This article describes a suitable technological process of repairing the defects on the casting using the welding technology. A specimen produced for this purpose was prepared by carving a groove into a cast steel plate 20 GL, which was then filled with a weld metal using MAG (135) technology. The following evaluation of the basic characteristics of the repaired site point to the suitability of the selected technological parameters of the repair procedure. Metallographic evaluation was carried out, further evaluation of mechanical properties by tensile test, bend test and Vickers hardness test. The proposed methodology for the evaluation repair of foundry defects in steel castings also meets the requirements for the approval of welding procedures in accordance with the relevant valid legislation.
Źródło:
Archives of Foundry Engineering; 2018, 18, 2; 177-180
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wear Resistance of Steel 20MnCr5 After Surfacing with Micro-jet Cooling
Autorzy:
Tarasiuk, W.
Piwnik, J.
Węgrzyn, T.
Sieteski, D.
Powiązania:
https://bibliotekanauki.pl/articles/380473.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
tribological properties
welding
micro-jet
steel 20MnCr5
właściwości tribologiczne
spawanie
mikrojety
stal 20MnCr5
Opis:
This paper presents results of experimental research concerning the impact of an innovative method of micro-jet cooling on the padding weld performed with MIG welding. Micro-jet cooling is a novel method patented in 2011. It enables to steer the parameters of weld cooling in a precise manner. In addition, various elements which may e.g. enhance hardness or alter tribological properties can be entered into its top surface, depending on the applied cooling gas. The material under study was steel 20MnCr5, which was subject to the welding process with micro-jet cooling and without cooling. Nitrogen was used as a cooling gas. The main parameter of weld assessment was wear intensity. The tests were conducted in a tribological pin-on-disc type position. The following results exhibit growth at approximately 5% in wear resistance of padding welds with micro-jet cooling.
Źródło:
Archives of Foundry Engineering; 2016, 16, 3; 121-124
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Micro-jet Cooling by Compressed Air after MAG Welding
Autorzy:
Węgrzyn, T.
Piwnik, J.
Tarasiuk, W.
Stanik, Z.
Gabrylewski, M.
Powiązania:
https://bibliotekanauki.pl/articles/381574.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
MAG
steel weld
welding
microjets
cooling
acicular ferrite
impact toughness
compressed air
stal stopowa
spawanie
udarność
chłodzenie
Opis:
The material selected for this investigation was low alloy steel weld metal deposit (WMD) after MAG welding with micro-jet cooling. The present investigation was aimed as the following tasks: analyze impact toughness of WMD in terms of micro-jet cooling parameters. Weld metal deposit (WMD) was first time carried out for MAG welding with micro-jet cooling of compressed air and gas mixture of argon and air. Until that moment only argon, helium and nitrogen and its gas mixture were tested for micro-jet cooling.
Źródło:
Archives of Foundry Engineering; 2016, 16, 2; 111-114
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structure and Mechanical Properties of the CO2 Laser Welded Joint of AZ91 Cast
Autorzy:
Dziadoń, A.
Musiał, E.
Powiązania:
https://bibliotekanauki.pl/articles/947599.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
AZ91 alloy
laser welding
porosity
microstructure
mechanical properties
stop AZ91
spawanie laserowe
porowatość
mikrostruktura
właściwości mechaniczne
Opis:
Plates of AZ91 cast magnesium alloy with a thickness of 3.5 mm were butt-welded using a laser power of 2000 W and helium as the shielding gas. The effect of the welding speed on the weld cross-sectional geometry and porosity was determined by microscopic analysis. It was found that to avoid the formation of macropores, welding should be carried out at a speed of 3.4 m/min or higher. Non-equilibrium solidification of the laser-melted metal causes fragmentation of the weld microstructure. Joints that were welded at optimal laser processing parameters were subjected to structural observations using optical and scanning microscopy and to mechanical tests. The mechanical properties were determined through Vickers hardness measurements in the joint cross-section and through tensile testing. The results indicate that the hardness in the fusion zone was about 20 HV (30%) higher than that of the base material. The weld proved to be a mechanically stable part of the joint; all the tensile-tested specimens fractured outside the fusion zone.
Źródło:
Archives of Foundry Engineering; 2020, 20, 3; 9-14
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
FSW Welding of Aluminium Casting Alloys
Autorzy:
Pietras, A.
Rams, B.
Powiązania:
https://bibliotekanauki.pl/articles/383129.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
aluminium casting
product development
casting defect
FSW process
aluminium
welding
stopy aluminium
rozwój produktów
wady odlewów
proces FSW
spawanie
Opis:
The article contains basic information associated with the impact of the FSW process parameters on the forming of a weld while friction welding of aluminium casting alloys. Research was conducted using specially made samples containing a rod of casting alloy mounted in the wrought alloy in the selected area of FSW tool acting. Research has thrown light on the process of joining materials of significantly dissimilar physical properties, such as casting alloys and wrought alloys. Metallographic testing of a weld area has revealed the big impact of welding conditions, especially tool rotational speed, on the degree of metal stirring, grain refinement and shape factor of a weld. As the result of research it has been stated that at the high tool rotational speed, the metals stirring in a weld is significantly greater than in case of welding at low rotational speeds, however this fails to influence the strength of a weld. Plastic strain occurring while welding causes very high refinement of particles in the tested area and changing of their shape towards particles being more equiaxial. In the properly selected welding conditions it is possible to obtain joints of correct and repeatable structure, however in the case of the accumulation of cavities in the casting alloy the FSW process not always eliminates them.
Źródło:
Archives of Foundry Engineering; 2016, 16, 2; 119-124
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Partially Melted Zone in Mg-Al Type Alloy After Gas-tungsten Arc Welding
Autorzy:
Braszczyńska-Malik, K. N.
Przełożyńska, E.
Mróz, M.
Powiązania:
https://bibliotekanauki.pl/articles/381760.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Mg-Al-Zn alloy
gas tungsten arc welding
partially melted zone
stop Mg-Al-Zn
spawanie łukowe
strefa przetopienia
Opis:
The gas-tungsten arc (GTA) welding behaviors of the commercial AZ91 magnesium alloy were examined in terms of microstructure characteristics. This study focused on the effects of the GTAW process parameters (like welding current, welding speed and method of additional cooling of the welded samples) on the size of the fusion zone (FZ) and partially melted zone (PMZ). The PMZ morphology of the eutectic regions changed from less to more divorced in the direction from the FZ to the base metal. The largest PMZ was obtained at a low welding speed (3.33 mm/s) and without additional water cooling of the samples.
Źródło:
Archives of Foundry Engineering; 2013, 13, 2 spec.; 18-21
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł

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