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Keywords = MMA welding

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16 pages, 5756 KiB  
Article
Corrosion Behavior and Mechanism of 304 Stainless Steel Welded Joints in Simulated Freshwater Environment
by Yue Yu, Xiayan Wang, Shilong Wei, Zengyao Chen, Zhanhua Wang, Mengnan Li and Zhiyong Liu
Materials 2025, 18(13), 3074; https://doi.org/10.3390/ma18133074 - 28 Jun 2025
Viewed by 398
Abstract
This investigation examines the corrosion behavior and mechanisms of 304 stainless steel shielded metal arc welding (SMAW) and gas metal arc welding (GMAW) joints in the simulated reservoir environment through electrochemical testing, stress-free hanging specimens and U-bend specimen immersion experiments, and microstructural characterization. [...] Read more.
This investigation examines the corrosion behavior and mechanisms of 304 stainless steel shielded metal arc welding (SMAW) and gas metal arc welding (GMAW) joints in the simulated reservoir environment through electrochemical testing, stress-free hanging specimens and U-bend specimen immersion experiments, and microstructural characterization. The electrochemical results demonstrate that both welded joints exhibit a superior corrosion resistance in this environment, with a sensitivity of intergranular corrosion (IGC) below 1% and a corrosion rate below 0.005 mm/a. Increasing chloride concentrations elevate the passivation current densities for both the base metal and welded joints. The immersion testing revealed that after 90 days of exposure across the investigated chloride concentrations (50–300 mg/L), all welded specimens maintained surface integrity with no visible corrosion. Furthermore, U-bend specimens demonstrated no evidence of stress corrosion cracking, confirming a low stress corrosion susceptibility. Full article
(This article belongs to the Section Corrosion)
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12 pages, 2287 KiB  
Article
Fracturing in 14MoV6-3 Steel Weld Joints—Including Base Metals—After a Short Time in Service
by Esmail Ali Salem Ahmed, Nenad Radović, Dragomir Glišić, Stefan Dikić, Nikola Milovanović, Mirjana Opačić and Jasmina Lozanović
Metals 2025, 15(5), 483; https://doi.org/10.3390/met15050483 - 25 Apr 2025
Viewed by 497
Abstract
In order to establish the influence of prolonged exposure to high temperatures on 14MoV6-3 steel, three different weld joints were designed. New-to-new material, new-to-used material, and used-to-used material joints were welded using two welding technologies—GTAW and a combination of GTAW + MMA. The [...] Read more.
In order to establish the influence of prolonged exposure to high temperatures on 14MoV6-3 steel, three different weld joints were designed. New-to-new material, new-to-used material, and used-to-used material joints were welded using two welding technologies—GTAW and a combination of GTAW + MMA. The weldments were tested by means of microstructure and tensile testing. The results showed that in all weldments, a fracture occurred in the base metal. Also, in the case of the new-to-used welded sample, the fracture always occurred in the used base metal. Since both materials have the same chemical composition, the difference in microstructure was related to long exposure to high temperatures. New steel has a considerably smaller grain size, while the used material underwent grain growth coupled with carbide coarsening, which decreased its strength. The yield strength (YS) of the new material was higher than the YS of the used material, which exhibited similar values in the used base metal and both weldments. It can be assumed that, since deformation starts in the area with the lowest yield point, the used material is the critical place in a given weldment. Therefore, the accurate extent of strength decrease cannot be evaluated based on the testing of new material, i.e., there is a need to reconsider the traditional qualifications of welding technology. Full article
(This article belongs to the Special Issue Fracture Mechanics and Failure Analysis of Metallic Materials)
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14 pages, 3570 KiB  
Article
Evaluation of the Corrosion Resistance of 904L Composite Plate in a High-Temperature and High-Pressure Gas Field Environment
by Shuai Wang, Ping Mei, Lijing Chang, Chao Wu, Shaoyun Chen, Qingguo Chen and Guangshan Li
Processes 2024, 12(11), 2372; https://doi.org/10.3390/pr12112372 - 29 Oct 2024
Cited by 2 | Viewed by 1209
Abstract
In order to study the corrosion resistance of 904L composite plate pressure vessels under a high-temperature and high-pressure gas field environment, the pitting corrosion and stress corrosion cracking resistance of a 904L composite plate body and weld material were compared with those of [...] Read more.
In order to study the corrosion resistance of 904L composite plate pressure vessels under a high-temperature and high-pressure gas field environment, the pitting corrosion and stress corrosion cracking resistance of a 904L composite plate body and weld material were compared with those of a 2205 composite plate and 825 composite plate, which are used in high-temperature and high-pressure gas field environments. The results showed that the pitting resistance of the 904L composite plate was lower than that of the 825 composite plate and higher than that of a 2205 solid-solution pure material plate and a 2205 composite plate. The corrosion resistance of the 625 welding material is higher than that of the E385 welding material. In the simulation of the corrosion environment of a high-temperature and high-pressure gas field, the corrosion rates of the 904L composite plate body, welding seam, and surfacing welding were all less than 0.025 mm/a, indicating slight corrosion, and the sensitivity coefficient of chloride stress corrosion cracking was less than 25%, indicating low sensitivity. The 904L composite plate met the requirements of corrosion resistance for pressure vessel materials in a high-temperature and high-pressure gas field environment. Full article
(This article belongs to the Section Materials Processes)
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13 pages, 4467 KiB  
Article
Using Metal Magnetic Memory to Evaluate the Effect of Welding Method and Weld Temperature on Magnetic Field Strength in Structural Steel
by Agata Wieczorska and Agnieszka Kosoń-Schab
Materials 2023, 16(15), 5256; https://doi.org/10.3390/ma16155256 - 26 Jul 2023
Cited by 2 | Viewed by 1396
Abstract
Tests of welds are carried out inter-operatively, during the execution of the steel structure, as well as after the structure is welded, but even before its assembly. Steel structures already in service are also examined to detect potential cracks, delamination, or corrosion loss [...] Read more.
Tests of welds are carried out inter-operatively, during the execution of the steel structure, as well as after the structure is welded, but even before its assembly. Steel structures already in service are also examined to detect potential cracks, delamination, or corrosion loss of thickness having the effect of weakening the mechanical strength of the structure. Such examinations are some the elements that comprise a structural health assessment. In this paper, the metal memory method was used to evaluate the effect of the welding method and weld temperature on the change in magnetic field strength. S235JR structural steel was used for the study, which was subjected to milling and MMA, TIG, and MIG welding. The results of measurement experiments carried out for each welding method are presented as graphs. Full article
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15 pages, 11461 KiB  
Article
Influence of Innovative Post-Weld Finishing Method on Bead Surface Quality
by Olha Dvirna, Agata Wieczorska, Norbert Abramczyk and Anna Lesnau
Materials 2023, 16(14), 5100; https://doi.org/10.3390/ma16145100 - 19 Jul 2023
Cited by 2 | Viewed by 1339
Abstract
The article describes an innovative post-weld surface finishing method, which is characterized by moving a specialized cutting tool along a butt weld. The aforementioned method is unique for the machining allowance, which is treated as the weld bead height and is removed in [...] Read more.
The article describes an innovative post-weld surface finishing method, which is characterized by moving a specialized cutting tool along a butt weld. The aforementioned method is unique for the machining allowance, which is treated as the weld bead height and is removed in one step with one pass of the cutting tool. The tool is equipped on one side with linearly arranged tooth-shaped cutting elements, with the adjacent teeth height changing and increasing according to the direction of the feed. The non-standard geometry of the cutting tool enables the finishing of a heterogeneous post-weld surface with increased hardness. The results of studying the 2D profile parameters and the 3D stereometric characteristics of the surface roughness using the optical method are presented in the article. Test samples were made of S235JR steel and butt welded with the MMA, MIG, and TIG methods. Subsequently, the welding bead was ground and finished in accordance with the innovative method to flush the bead and the base metal’s surface. Additionally, residual stress analyses were performed using the X-ray diffraction method in the surface layers of the test samples. Based on the conducted research, the influence of the innovative finishing method on the surface quality is described. Full article
(This article belongs to the Special Issue Manufacturing Technology: Materials, Innovations and Applications)
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20 pages, 12759 KiB  
Article
Catastrophic Impact Loading Resilience of Welded Joints of High Strength Steel of Refineries’ Piping Systems
by Andrzej Klimpel, Anna Timofiejczuk, Jarosław Kaczmarczyk, Krzysztof Herbuś and Massimiliano Pedot
Materials 2022, 15(4), 1323; https://doi.org/10.3390/ma15041323 - 11 Feb 2022
Cited by 1 | Viewed by 2442
Abstract
Refineries piping installation systems are designed, fabricated, and operated to assure very high levels of quality and structural integrity, to provide very high resilience to catastrophic events like earthquakes, explosions, or fires, which could induce catastrophic damage of piping systems due to collapse [...] Read more.
Refineries piping installation systems are designed, fabricated, and operated to assure very high levels of quality and structural integrity, to provide very high resilience to catastrophic events like earthquakes, explosions, or fires, which could induce catastrophic damage of piping systems due to collapse of nearby structures as towers, bridges, poles, walkways, vessels, etc. To evaluate the catastrophic impact loading resilience to failure of MMA (Manual Metal Arc Welding), GMA (Gas Metal Arc Welding), SSA (Self-shielded Arc Welding), and LASER+GMA of modern API 5L X80 pipes butt welded joints used for piping installation systems of refineries, the new, original technique of the quantitative and qualitative evaluation of impact loading resilience of butt welded joints of pipes was developed. The high-quality butt welded joints were impact loaded by the freely dropping 3000 kg mass hammer of the die forging hammer apparatus. The impact loading energy needed to exceed the yield strength of the extreme zone of welded joints and to induce catastrophic fracture of butt welded joints of API 5L X80 pipes was calculated using FEM (Finite Element Method) modeling of the impact loading process of tested butt welded joints of pipes. Results of the FEM modeling of impact loading technique of butt welded joints of piping systems indicate that it is a useful tool to provide valuable data for experimental impact loading tests of welded joints of pipes, decreasing the time and cost of the experiments. The developed impact loading technique of butt welded joints of pipes to simulate the catastrophic events in refinery piping systems and evaluate the resilience of the butt welded joints of pipes to catastrophic failure proved to be very efficient and accurate. Experiments of impact loading indicated that all specimens of butt welded joints API 5L X80 steel pipes are resilient to failure (cracks) in the extreme stressed/strained areas, above yield and tensile strength of the weld metals, no cracks or tears appeared in the extreme stressed/strained areas of the edges of the pipes, proving the very high quality of API 5L X80 steel pipes. Full article
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21 pages, 7771 KiB  
Article
Assessing MMA Welding Process Stability Using Machine Vision-Based Arc Features Tracking System
by Wojciech Jamrozik and Jacek Górka
Sensors 2021, 21(1), 84; https://doi.org/10.3390/s21010084 - 25 Dec 2020
Cited by 12 | Viewed by 6334
Abstract
Arc length is a crucial parameter of the manual metal arc (MMA) welding process, as it influences the arc voltage and the resulting welded joint. In the MMA method, the process’ stability is mainly controlled by the skills of a welder. According to [...] Read more.
Arc length is a crucial parameter of the manual metal arc (MMA) welding process, as it influences the arc voltage and the resulting welded joint. In the MMA method, the process’ stability is mainly controlled by the skills of a welder. According to that, giving the feedback about the arc length as well as the welding speed to the welder is a valuable property at the stage of weld training and in the production of welded elements. The proposed solution is based on the application of relatively cheap Complementary Metal Oxide Semiconductor (CMOS) cameras to track the welding electrode tip and to estimate the geometrical properties of welding arc. All measured parameters are varying during welding. To validate the results of image processing, arc voltage was measured as a reference value describing in some part the process stability. Full article
(This article belongs to the Special Issue Sensor Fusion for Object Detection, Classification and Tracking)
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14 pages, 4209 KiB  
Article
Analysis of Influence of the Welding Procedure on Impact Toughness of Welded Joints of the High-Strength Low-Alloyed Steels
by Andreja Ilić, Ivan Miletić, Ružica R. Nikolić, Vesna Marjanović, Robert Ulewicz, Blaža Stojanović and Lozica Ivanović
Appl. Sci. 2020, 10(7), 2205; https://doi.org/10.3390/app10072205 - 25 Mar 2020
Cited by 13 | Viewed by 4322
Abstract
This paper presents results of comparison of two welding procedures’ influence on selected properties of the welded joints of high-strength low-alloyed steel (HSLA), specifically the impact toughness and the hardness distribution in the specific zones of “single V” butt multiple-pass welded joints. Based [...] Read more.
This paper presents results of comparison of two welding procedures’ influence on selected properties of the welded joints of high-strength low-alloyed steel (HSLA), specifically the impact toughness and the hardness distribution in the specific zones of “single V” butt multiple-pass welded joints. Based on results obtained from experiments, the two applied welding technologies were evaluated. They differ by the welding grove geometry and by the applied root pass welding procedure. Both procedures use MAG (Metal Active Gas) welding for execution of the filling and covering passes, while the root passes are executed by the MMA (Manual Metal Arc) procedure in the first case and by the MIG (Metal Inert Gas) procedure in the second. Experimentally obtained values of the fracture energy of the welded samples for both procedures were smaller than the values for the parent metal, which confirms the fact that welding causes degradation of the mechanical properties of HSLA steel; thus, any welding technology parameters must be so selected to mitigate this deficiency. Full article
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12 pages, 5217 KiB  
Article
Analysis of Selected Properties of Welded Joints of the HSLA Steels
by Ivan Miletić, Andreja Ilić, Ružica R. Nikolić, Robert Ulewicz, Lozica Ivanović and Norbert Sczygiol
Materials 2020, 13(6), 1301; https://doi.org/10.3390/ma13061301 - 13 Mar 2020
Cited by 37 | Viewed by 3759
Abstract
This paper presents research of the impact toughness and hardness distribution in specific zones of a ‘single V’butt multiple-pass welded joints of the high-strength low-alloyed steels. Obtained values of the impact toughness are analyzed in correlation with a microstructure in specific zones of [...] Read more.
This paper presents research of the impact toughness and hardness distribution in specific zones of a ‘single V’butt multiple-pass welded joints of the high-strength low-alloyed steels. Obtained values of the impact toughness are analyzed in correlation with a microstructure in specific zones of the welded joint, together with the micro hardness distribution found in the related zones. Based on the carried out analysis and results obtained in experiments, the applied technology of welding was evaluated. The original conclusions on influence of the selected welding procedure manual metal arc (MMA) for the root passes and metal active gas (MAG) for the filling and covering passes) on impact toughness of the high-strength low-alloyed steels are drawn. The paper also presents discussion on the valid standards and recommendations related to welding of those steels, from the aspect of applications in design of steel welded constructions. Full article
(This article belongs to the Special Issue Manufacturing and Fatigue Properties of Materials)
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15 pages, 6486 KiB  
Article
Properties and Structure of Deposited Nanocrystalline Coatings in Relation to Selected Construction Materials Resistant to Abrasive Wear
by Jacek Górka, Artur Czupryński, Marcin Żuk, Marcin Adamiak and Adam Kopyść
Materials 2018, 11(7), 1184; https://doi.org/10.3390/ma11071184 - 10 Jul 2018
Cited by 24 | Viewed by 5689
Abstract
Presented in this work are the properties and structure characteristics of MMA (Manual Metal Arc) deposited nanocrystalline coatings (Fe-Cr-Nb-B) applied to an iron nanoalloy matrix on an S355N steel substrate in relation to selected construction materials resistant to abrasive wear currently used in [...] Read more.
Presented in this work are the properties and structure characteristics of MMA (Manual Metal Arc) deposited nanocrystalline coatings (Fe-Cr-Nb-B) applied to an iron nanoalloy matrix on an S355N steel substrate in relation to selected construction materials resistant to abrasive wear currently used in industry. The obtained overlay welds were subjected to macro and microscopic metallographic examinations; grain size was determined by X-ray diffraction (XRD), and chemical composition of precipitates was determined by energy-dispersive X-ray spectroscopy (EDS) during scanning electron microscopy (SEM). The size of the crystalline grains of the Fe-Cr-Nb-B nanocrystalline microstructure was analyzed using an Xpert PRO X-ray diffractometer. Analysis of the test results of the obtained layers of arc-welded Fe-Cr-Nb-B-type alloy confirmed that the obtained layers are made of crystallites with a size of 20 nm, which classifies these layers as nanocrystalline. The obtained nanocrystalline coatings were assessed by hardness and with the use of metal-mineral abrasion testing. The results of the coatings’ properties tests were compared to HARDOX 400 alloy steel. Full article
(This article belongs to the Special Issue Welding, Joining and Coating of Metallic Materials)
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