Wyniki wyszukiwania - BazTech

1

Zagrożenia oczu podczas ręcznego spawania laserowego - analiza metod wyznaczania ekspozycji na promieniowanie laserowe

Owczarek Grzegorz, Szkudlarek Joanna, Jachowicz Marcin, Okrasa Małgorzata

Bezpieczeństwo Pracy : nauka i praktyka

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2024

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nr 3

22-27

PL

Ręczne spawanie laserowe, które jest jednym z najnowszych rozwiązań w technologii spawalniczej, stwarza specyficzne zagrożenia zawodowe, zwłaszcza dla oczu spawaczy narażonych na szkodliwe promieniowanie optyczne. Pomimo powszechnego zastosowania tej technologii brakuje jednoznacznych i spójnych metod szacowania ryzyka zawodowego. Ten artykuł ma na celu wypełnienie owej luki poprzez analizę różnych metod wyznaczania maksymalnej dopuszczalnej i spodziewanej ekspozycji (MDE) na promieniowanie laserowe oraz określania wymaganego poziomu ochrony dla filtrów zabezpieczających przed promieniowaniem laserowym. Wyniki analizy mogą pomóc w tworzeniu skuteczniejszych protokołów bezpieczeństwa dla spawaczy wykonujących ręczne spawanie laserowe, co ma kluczowe znaczenie dla ich zdrowia i bezpieczeństwa.

EN

Manual laser welding, one of the latest advancements in welding technology, poses specific occupational hazards, particularly for welders' eyes exposed to harmful optical laser radiation. Despite the widespread use of this technology, there is a lack of clear and consistent methods for assessing occupational risk. This article aims to fill this gap by analyzing various methods of determining the maximum permissible and expected exposure to laser radiation, as well as defining the required protection level for filters protecting against laser radiation. The results of this analysis may assist in creating more effective safety protocols for welders conducting manual laser welding, which is crucial for their health and safety.

2

Kontrola głębokości wtopienia w czasie rzeczywistym w procesie spawania laserowego z wykorzystaniem interferometrycznego pomiaru odległości. Cz. I

Chrobak Grzegorz, Stano Sebastian, Lisiecki Aleksander

Stal, Metale & Nowe Technologie

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2023

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nr 11-12

8--13

PL

Kontrola jakości złączy spawanych jest kluczowym czynnikiem zapewnienia bezpieczeństwa spawanych podzespołów i całych konstrukcji, niezależnie od branży, wykonywanego produktu i zastosowanej metody spawania.

3

Analiza zastosowania sztucznej inteligencji w produkcji spawalniczej. Cz. II

Klimpel Andrzej

Stal, Metale & Nowe Technologie

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2023

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nr 5-6

24--31

PL

Artykuł opisuje podstawy zastosowania sztucznej inteligencji, wykorzystującej nowoczesne systemy komputerowe do budowy cyfrowych bliźniaków, uczenia maszynowego, głębokiego uczenia wraz z architekturą głębokich sieci neuronowych.

4

Laserowe spawanie stali niskowęglowej

Radek Norbert

Obróbka Metalu

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2023

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nr 2

29--37

PL

W pracy przestawiono badania wpływu wybranych parametrów spawania laserowego na własności mechaniczne spoiny. Badano wpływ dwóch parametrów: prędkości posuwu oraz mocy wiązki. Na badania własności spoiny oraz stref do nich przyległych składały się następujące pomiary: statycznej próby rozciągania i twardości oraz obserwacje mikroskopowe. Przeprowadzone badania wykazały, że spoiny otrzymane przy różnych parametrach spawania charakteryzują się zbliżonymi własnościami mechanicznymi.

EN

In the paper studies of the influence of selected laser welding parameters on the mechanical λproperties of welds is presented. The study examined the effect of two parameters: feed speed and beam power. The tests of the properties of the weld and the adjacent zones consisted of the following measurements: static tensile test, hardness and microscopic observations. A TRUMPF CO2 laser, Lasercell 1005 (wavelength λ = 10, 6 μm) was used for welding. The samples were made of 0,8 mm thick DC04 low carbon steel. The static tensile test was carried out on the LabTest 5. 20SP1 tensile and compressive test bench. The hardness tester NEXUS 4304 was used to the hardness tests. Microscopic observations were performed using a Joel scanning microscope type JSM-5400. Conducted tests show that welds obtained with different welding parameters are characterized by similar mechanical properties.

5

Laser welding of hot stamping blanks

Wróbel Ireneusz, Danielczyk Piotr

Mechanik

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2023

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R. 96, nr 4

37--41

EN

The article presents technological tests of laser welding of flat blanks of the same thickness, made of two types of hot-stamping steel. Special equipment for welding blanks was shown. Tests of laser welding of 2 mm thick blanks of two types of Usibor 1500 and Usibor 2000 steel with different parameters were carried out. Smooth tensile specimen were cut out of the welded blanks. The obtained microstructure and hardness tests were performed. The research results were discussed.

PL

W artykule opisano próby technologiczne laserowego spawania płaskich formatek o tej samej grubości, wykonanych z dwóch rodzajów stali do tłoczenia na gorąco. Pokazano oprzyrządowanie do spawania formatek. Przeprowadzono testy laserowego spawania formatek o grubości 2 mm z dwóch rodzajów stali - Usibor 1500 i Usibor 2000, przy różnych parametrach procesu. Z zespawanych formatek wycięto próbki wiosełkowe do badań wytrzymałościowych. Wykonano badania uzyskanej mikrostruktury oraz twardości. Omówiono wyniki badań.

6

Spawanie hybrydowe (HLAW) laser + mig złączy stopów aluminium z serii 6XXX

Urbańczyk Michał

Maszyny Elektryczne : zeszyty problemowe

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2023

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Nr 1 (128)

109--113

PL

W artykule opisano zalety innowacyjnej metody spawania hybrydowego laser + MIG. Przedstawiono wyniki badań własnych dotyczących spawania hybrydowego złączy doczołowych 5+5 mm ze stopu aluminium EN AW 6082 oraz wyniki badań wytrzymałości uzyskanego złącza. Badania wykazały, że proces spawania hybrydowego pozwala uzyskać złącza charakteryzujące się równomiernym gładkim licem i prawidłowo uformowaną granią spełniając wymagania poziomu jakości B wg normy PN-EN ISO 10042. Przeprowadzone badania metalograficzne makroskopowe nie ujawniły pęcherzy gazowych w spoinie. Badanie złącza doczołowego blach z aluminium o grubości 5 + 5 mm wykazało, że spełnia ono wymagania normy PN-EN ISO 15614-14.

EN

The article presents the advantages of the innovative laser + MIG hybrid welding method. The article present shows the results of own research on the hybrid welding of 5+5 mm butt joints of aluminum alloy EN AW 6082 and the results of strength tests of the obtained joint. The research revealed that the hybrid welding process makes it possible to obtain quality butt joints with the uniform face and the properly formed root (meeting the requirements of quality level B according to PN-EN ISO 10042). The macroscopic tests carried out did not reveal gas pores in the weld. Testing of the butt joint of 5 + 5 mm thick aluminum plates showed that it met the requirements of PN-EN ISO 15614-14.

7

The assessment of the effect of technological conditions of the laser and hybrid welding of corrosion-resistant steels on welding fume emission

Wyciślik-Sośnierz Joanna, Matusiak Jolanta, Adamiec Janusz

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2023

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Vol. 67, No. 3

26--34

EN

Corrosion-resistant steels are used in many industrial sectors, including the food, chemical, petrochemical, power engineering and the building engineering industry. Welding processes constitute the main method enabling the joining of corrosion-resistant steels. Typically, corrosion-resistant steels are joined using manual metal arc welding, gas-shielded metal arc welding (MIG/MAG), flux-cored arc welding, TIG welding and submerged arc welding processes. In turn, advanced welding processes include laser beam, hybrid (laser + arc), plasma arc and electron beam welding methods. The growing popularity of laser methods in enterprises has necessitated the determination of the effect of technological conditions on the emission of welding fume, i.e. the dominant risk factor when welding corrosion-resistant steels. In 2017, welding fume (formed through the condensation and oxidation of metal vapours) was rated among factors of proven carcinogenic effect (in accordance with the requirements of the International Agency for Research on Cancer (IARC).

PL

Stale odporne na korozję znajdują zastosowanie w wielu gałęziach przemysłu, m.in. spożywczym, chemicznym, petrochemicznym, energetycznym oraz w budownictwie. Główną metodą łączenia stali odpornych na korozję są procesy spawalnicze. Do klasycznych metod spawania tych stali zalicza się spawanie elektrodami otulonymi, spawanie elektrodą topliwą w osłonie gazowej (MIG/ MAG), spawanie drutami proszkowymi, spawanie metodą TIG i spawanie łukiem krytym, natomiast do nowoczesnych metod spawania tych stali zalicza się spawanie: laserowe, hybrydowe (laser + łuk), plazmowe oraz elektronowe. To właśnie rosnący udział metod laserowych w przedsiębiorstwach spowodował konieczność określenia wpływu warunków technologicznych na wielkość emisji pyłu, bowiem jest to dominujące zagrożenie podczas spawania stali odpornych na korozję. Pył spawalniczy powstaje w wyniku kondensacji i utleniania par metalu. W 2017 roku został on zaklasyfikowany do grupy czynników o udowodnionym działaniu kancerogennym, zgodnie z wymogami Międzynarodowej Agencji Badań nad Rakiem (IARC).

8

Application of advanced welding methods in the production of rims for special purposes

Wojtaszak Maciej, Baluch Katarzyna, Łyczkowska Katarzyna, Urbańczyk Michał, Adamiec Janusz

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2023

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Vol. 67, No. 2

14--23

EN

Special rims belong to structural elements determining the safety and service life of vehicles. Because of the fact that welded joints are integral parts of rims, the quality of the former affects the service life of the entire element. In turn, welding, as a special process, is decisive for the quality of joints. Advanced high-performance welding methods (such as laser or hybrid welding) can increase the efficiency and improve the quality of welded joints. The article presents results of technological tests involving the laser and hybrid welding of steel grades DD11 and DD14 (used in the production of rims). The reference technology was MAG welding. The welded joints were subjected to non-destructive and destructive tests. The test results revealed that both laser and hybrid welding enabled the obtainment of joints meeting strength-related requirements. However, the laser welding process led to the lowering of the weld face and the formation of significant weld porosity.

PL

Felgi specjalne należą do elementów konstrukcyjnych pojazdów decydujących o bezpieczeństwie i trwałości ich użytkowania. Złącza spawane są integralną częścią felgi, co powoduje, że od ich jakości zależy trwałość całego elementu. Spawanie jest procesem specjalnym, który decyduje o wykonanym złączu. Zwiększenie wydajności i jakości złączy spawanych mogą zapewnić nowoczesne, wysoko wydajne metody spawania, do których zaliczyć można spawanie laserowe i spawanie hybrydowe. W artykule przedstawiono wyniki prób technologicznych spawania laserowego i spawania hybrydowego stali stosowanych na felgi specjalne w gatunkach DD11 i DD14, przyjmując jako technologię odniesienia obecnie stosowany proces spawania MAG. Wykonano badania nieniszczące i niszczące połączeń spawanych. Na podstawie wyników tych badań stwierdzono, że zarówno spawanie laserowe, jak i hybrydowe zapewniają uzyskanie złączy spełniających kryteria wytrzymałościowe; w przypadku spawania laserowego ujawniono jednak zaniżenie lica spoiny oraz liczne pęcherze.

9

Structure-property relationships and corrosion behavior of laser‑welded X‑70/UNS S32750 dissimilar joint

Maurya Anup Kumar, Pandey Shailesh M., Chhibber Rahul, Pandey Chandan

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 2

art. no. e81, 2023

EN

This research aims to study the microstructure characteristics, mechanical properties, and corrosion behaviors of the dissimilar autogenous laser beam welded joint of pipeline steel (X-70) and super duplex stainless steel (sDSS 2507). Pipelines for the transmission of oil and gas and risers for offshore oil and gas drilling require this dissimilar joint. A dissimilar joint must maintain its properties and be defect-free under such challenging operating conditions. The microstructure of the interface, weld zone and heat-affected zone (HAZ) were all investigated thoroughly using optical microscopy (OM) and scanning electron microscopy (SEM) equipped with energy-dispersive spectroscopy (EDS). This dissimilar joint had signifcant microstructure anomalies in the weld and interfaces. Microstructure inhomogeneity’s effect on welded joint mechanical properties, including microhardness, tensile and impact strength, was also studied. The linear potentiodynamic polarisation test in neutral 3.5 wt.% NaCl solution was used to study this weldment’s corrosion behavior. The corroded surfaces were examined using an OM and SEM for the surface morphology investigation of corroded specimens. The macro-optical investigation has revealed full penetrations in the weld without any inclusions or porosities. The interface between the sDSS 2507 weld zone and the X-70 coarse grain heat-affected zone (CGHAZ) indicated a peak hardness of 418 Hv0.5. With an average of 345 Hv0.5, the WZ’s hardness variation was reported to be in the 298-420 Hv0.5 range. The hardness of the X-70/sDSS 2507 weld interface was assessed to be greater than that of the other region of weldments. An untempered martensitic region in WM and the CGHAZ of X-70, and the presence of M-A components are credited with the increase in hardness. The welded joint achieved reasonably excellent strength and ductility and met the marine and offshore standards requirements. The base metals and weldment for X-70 and sDSS 2507 have respective ultimate tensile strengths (UTS) of 610±6 MPa, 995±8 MPa, and 675±10 MPa. The tensile findings revealed that the fracture location for weldment was evident in the X-70 base metal, ensuring that the weld metal was of adequate strength for the laser-weld joints. It was observed that the weldment’s WM had the lowest impact strength. The Charpy impact toughness of the weld metal, however, was higher than both the ASME standard (>41 J) and the EN 1599:1997 standards (>47 J). The sDSS 2507 BM (310±4 J) clearly outperforms the weld zones (185±3 J) and X-70 base metal (295±2 J) in terms of impact strength. The electrochemical corrosion test shows the corrosion potential, and the weld zone's corrosion rate is between sDSS 25,070 (- 260±1.3 mV, 0187±0.002 mm/year) and X-70 base metal (- 454±1.8 mV, 0.321±0.017 mm/year). Additionally, the surface morphologies and the electrochemical measurements matched significantly.

10

Investigations of the structure and hardness of dissimilar steel-to-aluminum joints made using laser welding technology

Misiura Karolina, Konieczny Jarosław, Labisz Krzysztof, Boris Renata

Transport Problems

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2022

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T. 17, z. 1

73--86

EN

Since welding technology is currently used to assemble the frame of driver’s seats, it is important to develop laser welding technology for steel and aluminium. For this reason, the purpose of the present work was to examine the structure and selected properties of aluminium-steel joints using the example of an EN AW-6060 aluminium alloy and DC04 low-alloy steel welded in laser technology. Overlapping joints were made, weld type -following the hole laser welding method -laser beam (LB) using a high power disk laser (TRUMPF TruDisk3302), in which the active medium is a yttrium-aluminium crystal (YAG). Metallographic microstructure investigations were carried out using a light microscope from Carl Zeiss - Observer Z1m, and the weld microstructures were investigated using an SEM Supra 35 microscope, also from Carl Zeiss. The chemical composition analysis in micro-areas was carried out using an X-ray energy dispersion spectrometer from EDAX, which was a part of the SEM Supra 35. The hardness of the substrate material and the welded area was measured following the Vickers method using an FM-ARS 9000 micro hardness tester from Tokyo, Japan. It was found that there is a potential for commercial use of laser welding to make a low-carbon steel-aluminium alloy joint. During the formation of the weld in its microstructure, intermetallic compounds of the FexAly type were created, which significantly reduced the mechanical and plastic properties of the joint. The hardness of the weld created wasabout seven times higher than that of DC04 carbon steel. The choice of laser welding parameters (primarily, laser power and beam speed) significantly impacted the weld structure and properties.

11

Development of mathematical and numerical models for the analysis of overlap laser beam welding of dissimilar materials

Domański Tomasz, Piekarska Wiesława, Saternus Zbigniew, Kubiak Marcin

Journal of Applied Mathematics and Computational Mechanics

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2022

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Vol. 21, nr 2

15--26

EN

The welding process of dissimilar materials causes a lot of technological issues related to different properties of materials of joined elements. Thermal conductivity is one of most important factors influencing the deformation of the weld. The change of thermal conductivity in the function of the temperature can produce various strains that cannot be predicted during construction design. Different structures of materials appear during joining of dissimilar materials as well as different characteristic zones of the joint and its mechanical properties. The most important is the proper identification of joint zones and the size of deformation at the production stage of welded construction. This work presents the numerical analysis of physical phenomena in overlap welding of two sheets made of S355 carbon steel and 304 austenitic steel using a laser beam. A three-dimensional discrete model is developed taking into account thermophysical properties changing with temperature. Temperature distribution and the shape of the welding pool is predicted on the basis of performer computer simulations. The influence of thermal load on the formation of stress and strain fields is determined.

12

Laser welding of high-strength steel S960QL

Kurc-Lisiecka Agnieszka, Lisiecki Aleksander

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2022

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Vol. 66, No. 3

37--48

EN

The article discusses the results of tests concerning the effect of parameters used during the basic bead-on-plate laser welding (i.e. location of the laser beam focus, welding rate and linear welding energy) of 4.0 mm thick sheets made of high-strength steel S960QL on the quality and properties of simulated butt joints. The welding tests were performed using a YAG TruDisk 3302 Yb disk laser (TRUMPF) having a maximum output power of 3.3 kW and provided with a head focusing the laser beam spot to a diameter of 200 μm. The simulated butt welded joints were made without the filler metal, using a technique which consisted in the laser beam melting of sheets. Macroscopic and microscopic tests as well as impact strength tests, fractographic tests and microhardness measurements involved the cross-section of the simulated specimens.

PL

W artykule opisano wyniki badań wpływu podstawowych parametrów spawania laserowego (tj. położenia ogniska wiązki laserowej, prędkości spawania oraz energii liniowej spawania) blach o grubości 4,0 mm ze stali o wysokiej wytrzymałości S960QL na jakość i właściwości symulowanych złączy doczołowych. Próby spawania wykonano za pomocą lasera dyskowego Yb:YAG TruDisk 3302 firmy TRUMPF o mocy maksymalnej 3,3 kW z głowicą ogniskującą wiązkę do średnicy 200 μm. Symulowane złącza doczołowe blach spawano bez materiału dodatkowego techniką polegającą na przetapianiu blach wiązką laserową. Wykonano badania makro- i mikroskopowe, próby udarności, badania fraktograficzne oraz pomiary mikrotwardości na przekroju poprzecznym próbek.

13

Laser welding of ferritic stainless steel 1.4509 used in the manufacturing of catalyst housings and diesel particulate filters

Lisiecki Aleksander, Rokita Zbigniew, Ginalski Dariusz, Kośny Andrzej, Pakieła Wojciech

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2022

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Vol. 66, No. 3

7--17

EN

The article discusses the results of tests as well as quality assessments of test joints made of tubes having a nominal thickness of 1.5 mm, a rectangular cross-section and a width of 140 mm and a length of 240 mm, made of ferritic stainless steel grade 1.4509 with the addition of microagents and used in the production of catalyst housings and diesel particulate filters. Test joints were made using a prototype line equipped with a TruDisk 2002 disk laser (TRUMPF) at a ROCH production plant in Tarnowskie Góry. The tests involved the preparation of an experimental batch of tubes. The tubes used in the tests were subjected to various procedures, i.e. only to laser welding (5 specimens), to the rolling of the weld surface after laser welding (5 specimens) and to the additional heat treatment of the joint area after welding (5 specimens). Most of the test welded joints represented high quality level B and were characterised by tensile strength not lower than that of the base material as well as by high plasticity confirmed in the Erichsen cupping test. However, slight undercuts of the weld root revealed in the tests indicated the risk of the partial lack of penetration or the formation of excessive undercuts in the production process. The foregoing necessitates the strict application of the welding procedure and, in particular, the ensuring of the high precision of laser beam positioning and accuracy when preparing sheet edges before welding.

PL

W artykule opisano wyniki badań i oceny jakości złączy próbnych rur o grubości nominalnej 1,5 mm, przekroju prostokątnym i szerokości 140 mm oraz długości 240 mm ze stali nierdzewnej ferrytycznej z mikrododatkami gatunku 1.4509, przeznaczonych do wytwarzania obudów katalizatorów i filtrów cząstek stałych. Złącza próbne wykonano za pomocą prototypowej linii z laserem dyskowym TRUMPF TruDisk 2002 w zakładzie produkcyjnym ROCH w Tarnowskich Górach. Do badań przygotowano partię doświadczalną rur bezpośrednio po spawaniu laserowym, z rozwalcowaną powierzchnią spoiny oraz po dodatkowej obróbce cieplnej obszaru złącza. Większość badanych złączy próbnych charakteryzuje się wysokim poziomem jakości B, wytrzymałością na rozciąganie nie niższą od materiału rodzimego oraz wysoką plastycznością, potwierdzoną w próbie tłoczności. Jednak ujawnione nieznaczne podtopienia grani spoiny wskazują na ryzyko wystąpienia częściowego braku przetopienia lub nadmiernych podtopień w procesie produkcyjnym. Z tego względu konieczne jest ścisłe stosowanie procedury spawania, w szczególności zapewnienie wysokiej precyzji pozycjonowania wiązki laserowej oraz dokładności przygotowania krawędzi blach do spawania.

14

High-performance welding processes – comparison of properties and applications

Keitel Steffen, Aurin Amadeus, Mückenheim Uwe, Neef Hendrik

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2022

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Vol. 66, No. 5

7--13

EN

The increasingly high level of productivity entails the growing popularity of high-performance welding methods in production processes. In addition, increasingly high occupational safety-related requirements stimulate the development of automated welding processes. The article compares methods of arc and laser welding technologies as well as presents primary process parameters in relation to values assumed in designs and with reference to permissible tolerances.

PL

Ciągły wzrost poziomu wydajności produkcji prowadzi do coraz powszechniejszego stosowania wysokowydajnych technologii spawalniczych w procesie produkcyjnym. Ponadto, rosnące wymagania bezpieczeństwa pracy stymulują rozwój automatyzacji procesów spawalniczych. W artykule porównano technologie spawania łukowego i laserowego i przedstawiono podstawowe parametry tych procesów w odniesieniu do wartości zakładanych w projektach i dopuszczalnej tolerancji.

15

Assessment of gold with titanium alloy weldability in conditions of a dental technique laboratory

Jania G., Żmudzki J., Topolska S.

Archives of Materials Science and Engineering

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2022

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Vol. 118, nr 1

36--41

EN

Purpose: In dental practice, there is necessary to weld gold with titanium under the conditions of a dental technique laboratory, which is difficult. The aim was to assess the weldability of pure gold with the titanium alloy Ti6Al4V using a prosthetic laser welding machine. Design/methodology/approach: Gold wire in a diameter of 0.4 mm made with the use of a jewellery drawbar (GOLDPORT, Szczecin, Poland) was welded to a titanium alloy Ti6Al4V substrate of dental implant abutment screw (MegaGen). Dental laser welding parameters (Bego Laser Star T plus) were 230 V; 6.5 ms; 2.5 Hz; laser spot 0.3 mm, and argon blow. Samples were included in resin, ground (500-4000 SiC), polished (Al2O3 suspension) and etched (Kroll solution) per 20 s before observation under a light microscope. Findings: There were well-welded and poorly joined zones. The discontinuities and voids there were not visible or sparse next to the initial weld point. Dendritic structure at well-welded remelting zones and two-phase microstructure of titanium and Ti3Au phase were found. The heat-affected zone was about of 20 microns. Research limitations/implications: Light microscopy was used, and precise phase identification required further investigations. Weld strength assessment requires further micro-hardness and load-bearing ability tests. Weldability concerns the model system with pure gold. Practical implications: In the case of elements with dimensions below 0.4 mm, the use of a laser with a smaller spot should be considered for better control of the remelting zone and mechanical positioning of the elements in order to stabilize and avoid discontinuities and voids. Originality/value: Prosthetic laser welding with a laser spot about of 0.3 mm allows to obtain well-welded parts of 0.3 mm in diameter under stable stitching conditions and higher than 0.4 mm in dimensions.

16

Autogenous laser-welded dissimilar joint of ferritic/martensitic P92 steel and Inconel 617 alloy: mechanism, microstructure, and mechanical properties

Kumar Amit, Pandey Chandan

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 1

art. no. e39, 2022

EN

Dissimilar autogenous welding of ferritic/martensitic P92 steel and Inconel 617 alloy was conducted using the laser beam-welding process. The microstructure evolution such as element segregation, grain size, and precipitate morphology was investigated in different areas of the welded joint for as-welded (AW) and post-weld heat treatment (PWHT) condition by using optical microscopy (OM) and Field Emission Scanning Electron Microscopy (FE-SEM). The tensile strength at room temperature, microhardness variation, and Charpy V impact toughness was evaluated for the welded joint to study the effect of laser beam welding on mechanical properties. Finally, the fractured impact-tested specimen was characterized by FE-SEM. Microstructure observation showed the microstructure heterogeneity across the welded joint. A typical martensitic lath structure devoid of carbide precipitates was observed in P92 HAZ, while Inconel 617 HAZ exhibited the fine-equiaxed austenite grains of average size 24 ± 7 µm with Ti-enriched Ti(C, N) and Mo-enriched carbide precipitates. A columnar and cellular structure consisting of the alloying element segregation in the inter-dendritic areas was observed for the weld metal (WM) near the interface, while the interior WM showed the cellular and equiaxed dendrites along with particles of type NBC, TiC, and M23C6. Fairly good strength and ductility were obtained for the welded joint, and it qualified the ultra-supercritical (USC) boiler requirement. The WM was witnessed as the weakest part of the welded joint for impact strength. However, the impact strength of the WM (61 ± 2 J) was measured higher than the ASME standard value (> 41 J) and EN ISO 3580:2017 standard value (> 47 J) in the AW joint. After the PWHT, a drastic reduction in impact strength of WM (48 ± 3 J) was measured, and it was very close to EN ISO 3580:2017 recommended value of 47 J. The HAZ of P92 and Inconel 617 showed good impact strength for both AW and PWHT joints. The austenitic microstructure in WM exhibited the hardness of 150 ± 8 HV0.5, which was lower than the hardness of P92 and Inconel 617 base metal. The hardness in P92 HAZ was estimated higher than other regions of the weldments (WM and Inconel 617 HAZ). PWHT resulted in a drastic reduction in hardness of P92 HAZ, while WM (154 ± 7 HV0.5) and Inconel 617 HAZ showed a minute change in hardness value. The tensile strength of welded joints for the transverse tensile-tested specimen was also measured higher than the base metal, and fracture was observed in weaker parent metal, i.e., P92 steel for both AW and PWHT joint.

17

Microstructure and mechanical properties of Sc-modified AA2519-T62 laser beam welded butt joints

Kosturek Robert, Grzelak Krzysztof, Torzewski Janusz, Wachowski Marcin, Śnieżek Lucjan

Advances in Materials Science

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2022

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Vol. 22, nr 4(74)

57--69

EN

The fundamental aim of the research is to investigate the microstructure and mechanical properties of the AA2519-T62 laser beam welded joints obtained with various values of welding velocity. For the constant value of laser power (3.2 kW) three joints have been produced with various values of welding velocity: 0.8, 1.1, and 1.4 m/min. The joints have been subjected to microstructure analysis (including both light and scanning electron microscope), microhardness measurements, tensile tests, and fractography of tensile samples. The established values of joint efficiency contain within the range of 55-66% with the highest value (66%) reported for the joint obtained with 1.1 m/min welding velocity. The produced welds have noticeable participation of pores, which tends to increase together with the value of welding velocity. In all cases, the failure has occurred in the fusion zone by ductile fracture.

18

Study of microstructure, geometry and properties of laser beam welded joints made of S960QL structural steel and S304 corrosion-resistant steel

Śliwiński Piotr, Piotrowski Maciej

Welding Technology Review

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2021

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R. 93, nr 1

15--23

EN

Contemporary grades of structural steels are produced using a very advanced thermo-mechanical treatment processes, so their properties strongly depend on the obtained structure. Corrosion-resistant austenitic steels have a high hot cracking tendency. Therefore, it is advantageous to use welding technologies, such as laser welding, that limit the size of the joint and its heat-affected zones and thus the deformations caused by the welding process. Laser welding is also characterized by small amount of heat transferred into the material during the process which limits the hot cracking tendency. During the tests, 8 samples made of S960QL steel and S304 steel, were prepared using a Trumpf TruDisk 3302 laser welding device. The produced samples were subjected to macro- and microscopy metallographic tests. Static tensile test and bend test were also performed as well as a hardness Vickers test under a load of 100 N. Good quality joints were obtained, characterized by a small number of welding imperfections. All passed the tensile test, the rupture occurred in the base material of S304 steel. All joints passed the bend test. The hardness of the welded joints ranged from 430-480 HV.

PL

Współczesne gatunki stali konstrukcyjnych poddawane są bardzo zaawansowanym procesom obróbki cieplno-mechanicznej, przez co ich własności silnie zależą od uzyskanej mikrostruktury. Stale austenityczne odporne na korozję cechuje natomiast skłonność do pękania gorącego. Korzystne zatem jest zastosowanie technologii spawania, takich jak spawanie laserowe, ograniczających wielkość złącza oraz jego strefy wpływu ciepła, a co za tym idzie odkształcenia wywołane procesem spawania. Spawanie laserowe cechuje się również niskimi energiami liniowymi procesu ograniczającymi zjawisko pękania gorącego. Podczas badań przygotowano 8 złączy spawanych ze stali S960QL oraz stali S304wykonanych przy pomocy urządzenia do spawania laserowego firmy Trumpf, model TruDisk 3302. Wykonane złącza zostały poddane badaniom metalograficznym makro- oraz mikroskopowym, statycznej próbie rozciągania oraz zginania, a także dokonano pomiaru twardości metodą Vickersa pod obciążeniem 100 N. Uzyskano trwałe złącza o niewielkiej liczbie niezgodności. Wszystkie złącza pomyślnie przeszły próbę rozciągania, zerwania nastąpiły w materiale rodzimym stali S304. Wszystkie złącza pomyślnie przeszły próby zginania. Twardość spoin wahała się w zakresie 430-480HV.

19

Numerical analysis of laser-welded flange pipe joints in lap and fillet configurations

Danielewski Hubert, Skrzypczyk Andrzej, Zowczak Włodzimierz, Gontarski Dariusz, Płonecki Leszek, Wiśniewski Hubert, Soboń Dominika, Kalinowski Artur, Bracha Gabriel, Borkowski Krzysztof

Technical Transactions

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2021

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Vol. 118, iss. 1

art. no. e2021030

EN

This article presents a numerical analysis of laser-welded flange pipe joints. The presented results concern the welding of low carbon S235JR and stainless 316L steels using a CO2 laser in lap and fillet joint configurations. The estimation of welding parameters was achieved using Simufact Welding software and numerical simulation, where output power, feed rate, efficiency and intensity distribution (Gaussian parameter) were analysed. In accordance with the established model, a thermo-mechanical simulation was performed. The calculated joint geometries show good agreement with experiments; therefore, the obtained results were used to study selected joint properties of both joint types. Stress-strain distribution was estimated on the basis of thermomechanical analysis. Weld bead geometry obtained from numerical simulation was compared with the results from trial joints. The numerical model established for both joint configurations shows good agreement with experimental results and were assumed to be accurate. The results of the performed analysis shown some advantages of the use of this configuration of lap joints in flange pipe joints.

20

Bezpieczeństwo przy zagrożeniach podczas produkcji i obróbki metalu

Pieczonka Łukasz

Promotor BHP

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2021

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nr 10

16--23

PL

Każda wykonywana praca wiąże się z występowaniem różnych zagrożeń. Jednym z takich obszarów jest obróbka metali. Pracodawca cały czas musi monitorować ryzyko, a do tego niezbędna jest rzetelna ocena ryzyka.