Welding and Joining of Materials in Off-Shore and Energy Industry

Journal Name	Impact Factor	CiteScore	Launched Year	First Decision (median)	APC
Applied Sciences applsci	2.7	4.5	2011	16.9 Days	CHF 2400
Coatings coatings	3.4	4.7	2011	13.8 Days	CHF 2600
Journal of Manufacturing and Materials Processing jmmp	3.2	5.5	2017	14.2 Days	CHF 1800
Materials materials	3.4	5.2	2008	13.9 Days	CHF 2600
Metals metals	2.9	4.4	2011	15 Days	CHF 2600

19 pages, 6837 KiB

Open AccessArticle

Prediction of Mechanical Properties in the Sub-Critical Heat Affected Zone of AHSS Spot Welds Using Gleeble Thermal Simulator and Hollomon-Jaffe Model

by Abdelbaset R. H. Midawi, Oleksii Sherepenko, Dileep Chandran Ramachandran, Shima Akbarian, Mohammad Shojaee, Tingting Zhang, Hassan Ghassemi-Armaki, Michael Worswick and Elliot Biro

Metals 2023, 13(11), 1822; https://doi.org/10.3390/met13111822 - 29 Oct 2023

Viewed by 1097

Abstract

Measuring the mechanical properties of weld Heat Affected Zone (HAZ) remains one of the main challenges in the failure analysis of spot-welded components. Due to the small size of the HAZ and variation in the temperature history, different peak temperatures and cooling rates [...] Read more.

Measuring the mechanical properties of weld Heat Affected Zone (HAZ) remains one of the main challenges in the failure analysis of spot-welded components. Due to the small size of the HAZ and variation in the temperature history, different peak temperatures and cooling rates impose a range of phase transformations across the resistance spot weld. Among the HAZ sub-regions, the sub-critical HAZ (SCHAZ), which experiences temperatures below A_C1 (350–650 °C), usually shows a reduction in the hardness in most of the modern AHSS grades due to the martensite tempering phenomenon. SCHAZ softening may lead to strain localization during loading. Therefore, it is important to characterize the local properties of the SCHAZ region to accurately predict RSW failure. However, it is not feasible to extract standard mechanical test specimens out of the SCHAZ of the spot-welded structure due to its small size. In this work, the SCHAZ of the spot weld for two AHSS, 3G-980 and PHS-1500, was simulated using a Gleeble^® (Dynamic Systems Inc., 323 NY-355, Poestenkill, NY 12140, USA) 3500 thermo-mechanical simulator. An in-situ high-speed IR thermal camera was used to measure the entire temperature field during the Gleeble heat-treatment process, which allowed for the visualization of the temperature distribution in the gauge area. The temperature and hardness data were fit to a Hollomon-Jaffe (HJ) model, which enables hardness prediction in the SCHAZ at any given temperature and time. Using the HJ model, a heat treatment schedule for each material was chosen to produce samples with hardness and microstructure matching the SCHAZ within actual spot weld coupons. Tensile specimens were machined from the coupons heat treated using simulated heat treatment schedules, and mechanical testing was performed. The results showed that the 3G-980 SCHAZ has a slight increase in yield strength and tensile strength, compared to the base metal, due to the formation of fine carbides within the microstructure. In contrast, the SCHAZ of PHS-1500 showed a significant reduction in the yield and tensile strength with yield point elongation behavior due to the reduction of the martensite phase and an increase in carbide formation due to the tempering process. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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11 pages, 4448 KiB

Open AccessTechnical Note

Analysis of Foreign Substance Flow within the Weld Joint through Simulation in Pressurized Water Reactor Nuclear Fuel Rods

by Taehyung Na, Taehyeon Kim and Yongdeog Kim

Appl. Sci. 2023, 13(15), 8905; https://doi.org/10.3390/app13158905 - 02 Aug 2023

Viewed by 814

Abstract

The welding of end plugs to cladding tubes is a critical process in the manufacture of pressurized water reactor (PWR) nuclear fuel rods. The resistance butt welding method is commonly used for this purpose in production. In this paper, we present an analysis [...] Read more.

The welding of end plugs to cladding tubes is a critical process in the manufacture of pressurized water reactor (PWR) nuclear fuel rods. The resistance butt welding method is commonly used for this purpose in production. In this paper, we present an analysis of the flow of foreign substances within the weld joint during the tube-cap welding process of PWR nuclear fuel rods, using SORPAS 2D software. The welding process generates foreign substances such as oxide scales, welding fumes, and spatters, which can negatively impact the quality of the weld. Additionally, carbide-based ceramic materials with higher melting temperatures than the base metal have been found within the weld joint in some cases, which can also affect the quality of the weld. To simulate the intrusion of foreign substances with higher melting temperatures than the base material (zirconium alloy) during welding, we conducted a simulation and analyzed the flow of foreign substances. Based on this study, we expected to enhance the reliability and stability of the tube-cap welding process of PWR nuclear fuel rods. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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15 pages, 4528 KiB

Open AccessArticle

Effect of Increasing Oscillation Width on the Arc Characteristics and Droplet Transfer Behavior of X80 Steel in the Overhead Welding Position of Narrow Gap P-GMAW

by Yang Bao, Ruilei Xue, Jianping Zhou and Yan Xu

Metals 2023, 13(7), 1314; https://doi.org/10.3390/met13071314 - 23 Jul 2023

Viewed by 897

Abstract

In the welding process of thick plate narrow gap pulse gas metal arc welding (P-GMAW) overhead welding station, the arc characteristics and droplet transfer behavior that become more complex due to the combined effects of narrow gap groove, gravity, and welding torch oscillation. [...] Read more.

In the welding process of thick plate narrow gap pulse gas metal arc welding (P-GMAW) overhead welding station, the arc characteristics and droplet transfer behavior that become more complex due to the combined effects of narrow gap groove, gravity, and welding torch oscillation. The welding stability is more difficult to control. High-speed imaging and electrical signal acquisition systems were established to observe and record the arc behavior and droplet transfer during the welding process at different oscillation widths, further revealing the formation mechanism of welding seam in narrow gap P-GMAW overhead welding station. Research has found that with an increased oscillation width, the arc deflects towards the sidewall from a trumpet-shaped symmetrically distributed around the center of the groove at an increasing deflection angle, and the droplet transfer changes from one droplet per pulse to multiple droplets per pulse, resulting in defects such as lack of sidewall fusion and undercutting of the weld seam. Based on the welding process discussed in this study, it is recommended to use an oscillation width of 2.6 mm. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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21 pages, 5345 KiB

Open AccessArticle

Impact of Gas Metal Arc Welding Parameters on Bead Geometry and Material Distortion of AISI 316L

by Samir Khrais, Hadeel Al Hmoud, Ahmad Abdel Al and Tariq Darabseh

J. Manuf. Mater. Process. 2023, 7(4), 123; https://doi.org/10.3390/jmmp7040123 - 29 Jun 2023

Cited by 4 | Viewed by 2085

Abstract

This study investigates the impact of gas metal arc welding (GMAW) parameters on the bead geometry and material distortion of AISI 316L. Three parameters—arc current in ampere (A), filler feed rate (m/min), and gas composition—were modified at varying levels in order to examine [...] Read more.

This study investigates the impact of gas metal arc welding (GMAW) parameters on the bead geometry and material distortion of AISI 316L. Three parameters—arc current in ampere (A), filler feed rate (m/min), and gas composition—were modified at varying levels in order to examine their effects. This study sheds new light on MAG welding lines’ physical properties and behavior and highlights the influence of quaternary shielding gas compositions. Taguchi analysis, which includes signal-to-noise (S/N) ratio and analysis of variance (ANOVA), was utilized to analyze and optimize the welding parameters. This study found that arc current significantly impacts bead geometry, while the shielding gas composition has the most significant effect on angular distortion and transverse shrinkage. The optimal welding parameters for achieving the best bead height and width are 160 A, 3.5 m/min, G1, with a bead height of 4.89 mm, and 120 A, 3 m/min, G2, with a bead width of 6.69 mm. Moreover, the optimal welding parameters for minimizing both angular distortion and transverse shrinkage are 120 A, 4 m/min, G2, resulting in an angular distortion value of 0.0042° and a transverse shrinkage value of 0.0254 mm. This research has practical implications for improving welding performance and can contribute to the advancement of MAG and MIG welding in manufacturing applications. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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17 pages, 6995 KiB

Open AccessArticle

Effects of Oscillation Width on Arc Characteristics and Droplet Transfer in Vertical Oscillation Arc Narrow-Gap P-GMAW of X80 Steel

by Hongsheng Liu, Ruilei Xue, Jianping Zhou, Yang Bao and Yan Xu

Metals 2023, 13(6), 1057; https://doi.org/10.3390/met13061057 - 31 May 2023

Cited by 2 | Viewed by 982

Abstract

In fields, such as oil and gas pipelines and nuclear power, narrow-gap welding has often been used for the connection of thick and medium-thick plates. During the welding process, a lack of fusion was prone to occur due to groove size limitations, seriously [...] Read more.

In fields, such as oil and gas pipelines and nuclear power, narrow-gap welding has often been used for the connection of thick and medium-thick plates. During the welding process, a lack of fusion was prone to occur due to groove size limitations, seriously affecting the service safety of large structures. The vertical oscillation arc pulsed gas metal arc welding (P-GMAW) method was adopted for narrow-gap welding in this study. The influence of the oscillation width on arc morphology, droplet transfer behavior and weld formation during narrow-gap welding was studied. Oscillation widths from 0 to 4 mm were used to weld narrow-gap grooves with a bottom width of 6 mm. The results show that, in non-oscillation arc welding, the arc always presented a bell cover shape, and the droplet transfer was in the form of one droplet per pulse, while the sidewall penetration of the weld was relatively small, making it prone to a lack of fusion. With an increase in the oscillation width, the arc gradually shifted to the sidewall. The droplet transfer mode was a mixed transfer of large and small droplets, and the sidewall penetration continued to increase, which was conducive to the fusion of the sidewall. However, when the oscillation width was wider than 3 mm, it led to the phenomenon of the arc climbing to the sidewall, and the weld was prone to porosity, undercutting and other welding defects. The oscillation width has a major impact on the stability of the welding process in vertical oscillation arc narrow-gap welding. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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11 pages, 2205 KiB

Open AccessArticle

The Influence of Oscillation Parameters on the Formation of Overhead Welding Seams in the Narrow-Gap GMAW Process

by Yang Bao, Ruilei Xue, Jianping Zhou, Hongsheng Liu and Yan Xu

Appl. Sci. 2023, 13(9), 5519; https://doi.org/10.3390/app13095519 - 28 Apr 2023

Cited by 3 | Viewed by 1004

Abstract

Thick-walled X80 pipelines for oil and gas transportation are difficult to relocate due to their large size. In the process of narrow-gap overhead welding, welding defects, such as bulges and lack of sidewall fusion, can appear easily. To avoid these defects and to [...] Read more.

Thick-walled X80 pipelines for oil and gas transportation are difficult to relocate due to their large size. In the process of narrow-gap overhead welding, welding defects, such as bulges and lack of sidewall fusion, can appear easily. To avoid these defects and to improve the welding quality of thick-walled pipelines, the GMAW welding method is adopted in this paper. The formation characteristics of the weld and the influence of arc oscillation parameters, such as the oscillation width and sidewall dwell time, on the formation process of narrow-gap overhead welding seams are studied. In this research, it was found that, in the NG-GMAW overhead welding position, there was a downward trend in the middle of the formed surface of the weld pool. Defects, such as finger-shaped penetrations and lack of sidewall fusion, were prone to occur due to gravity. The increased oscillation width was beneficial for reducing the protrusion in the middle of the weld seam, but an excessive oscillation width can easily cause undercut defects. The sidewall dwell time has little effect on the protrusion in the middle of the weld seam, but it can increase sidewall penetration, thereby avoiding the occurrence of incomplete sidewall penetration. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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22 pages, 10680 KiB

Open AccessArticle

Superalloy—Steel Joint in Microstructural and Mechanical Characterisation for Manufacturing Rotor Components

by Bożena Szczucka-Lasota, Tadeusz Szymczak, Tomasz Węgrzyn and Wojciech Tarasiuk

Materials 2023, 16(7), 2862; https://doi.org/10.3390/ma16072862 - 04 Apr 2023

Viewed by 1349

Abstract

The structure of energy rotor components includes different structural materials in the sections, which are subjected to varying levels of thermal loading. The first component section has to include a precipitation-hardened nickel-based alloy, while the second one may be manufactured from other materials. [...] Read more.

The structure of energy rotor components includes different structural materials in the sections, which are subjected to varying levels of thermal loading. The first component section has to include a precipitation-hardened nickel-based alloy, while the second one may be manufactured from other materials. Due to the installation cost, the use of expensive nickel-based materials is not recommended for applications in sections with a lower degree of thermal loading. Therefore, this aspect is still actually from an engineering point of view and is discussed in the paper by means of manufacturing and experimental approaches. The paper follows the welding problems related to a hybrid joint made of superalloy (Alloy 59) and hard rusting steel (S355J2W+N steel). The problem is solved using the MIG process at various parameters. With respect to the joint quality, microstructural features and mechanical parameters of the examined zone are presented. In the case of microstructure analysis, the dendritic and cellular natures of austenite were dominant elements of the joint. Mechanical tests have expressed a 50% reduction in elongation of the steel and alloy steel weld and lowering mechanical parameters. Mechanical parameters of the joint were on the level of their values observed for the steel, while the hardening coefficient followed the hardening curve of the alloy. Decohesion of the steel and mixed weld has reflected the constant proportion of values of axial and shear stress components up to the total separation. It is noted the tensile curves of the alloy and alloy steel joint follow a very similar shape, reporting the same response on the monotonic tension. The materials can be analysed by applying constitutive equations at very similar values of their coefficients. The obtained results enabled elaborating and examining the MIG welding process for thick-walled structures (not smaller than 8 mm) in detail giving all parameters required for technology. Finally, the technology for producing a hybrid joint using difficult-to-weld materials with different physical and mechanical properties, such as nickel alloys and low-alloy steels, is proposed. Results have shown it possible to develop a technology for producing of hybrid joints (supper alloy + hard rusting steel) with assumed physical and mechanical properties for rotors applied in the power boiler. This solution was proposed instead of previously used elements of rotors from expensive materials. It was assumed that the newly proposed and utilised method of welding will allow for obtaining good properties in terms of energy devices. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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13 pages, 33634 KiB

Open AccessArticle

Study on the Influence of Weld Spacing on the Tensile Strength of Laser Double-Pass Reciprocating Welding of DP780/6061-T6 Dissimilar Metals

by Yaowu Zhao, Xueqian Qin, Yuhong Long, Jia Zhou and Hui Jiao

Materials 2023, 16(7), 2560; https://doi.org/10.3390/ma16072560 - 23 Mar 2023

Viewed by 1106

Abstract

The welding of steel–aluminum dissimilar metals plays a vital role in promoting automobile lightweight. However, it is tricky to obtain good mechanical properties of steel–aluminum laser weldments. Based on the principle of preheating welding, the laser double-pass reciprocating welding method of steel–aluminum dissimilar [...] Read more.

The welding of steel–aluminum dissimilar metals plays a vital role in promoting automobile lightweight. However, it is tricky to obtain good mechanical properties of steel–aluminum laser weldments. Based on the principle of preheating welding, the laser double-pass reciprocating welding method of steel–aluminum dissimilar metals was proposed. In the experiment, different weld spacing such as 0, 0.5, 1.0, 1.5, and 2.0 mm were set, and numerical calculations of the temperature field of the molten pool were carried out. The results show that the tensile strength of weldment depends on the mechanical properties of the second weld seam in the optimal welding parameters. Compared with other weld spacing, when the weld spacing is 1.5 mm, the preheating temperature, peak temperature, and pool width on the steel side of the second weld are lower. In contrast, the weld penetration’s peak value and molten pool center’s temperature reach the maximum on the aluminum side. The thickness of the steel/aluminum transition layer changed from 14 to 11 to 8 μm with increased weld spacing. Moreover, the fracture mode of the second weld is a ductile fracture. Furthermore, the average tensile strength can reach 76.84 MPa. The results show that appropriate weld spacing and preheating temperature can effectively improve the tensile strength of the welding joint. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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13 pages, 9752 KiB

Open AccessArticle

The Joining of Alumina to Hastelloy by a TiZrCuNi Filler Metal: Wettability and Interfacial Reactivity

by Andrea Baggio, Fabiana D’Isanto, Fabrizio Valenza, Sofia Gambaro, Valentina Casalegno, Milena Salvo and Federico Smeacetto

Materials 2023, 16(5), 1976; https://doi.org/10.3390/ma16051976 - 28 Feb 2023

Cited by 1 | Viewed by 1391

Abstract

A systematic microstructural characterization of alumina joined to Hastelloy C22^® by means of a commercial active TiZrCuNi alloy, named BTi-5, as a filler metal is reviewed and discussed. The contact angles of the liquid BTi-5 alloy measured at 900°C for the two [...] Read more.

A systematic microstructural characterization of alumina joined to Hastelloy C22^® by means of a commercial active TiZrCuNi alloy, named BTi-5, as a filler metal is reviewed and discussed. The contact angles of the liquid BTi-5 alloy measured at 900°C for the two materials to be joined are 12° and 47° for alumina and Hastelloy C22^® after 5 min, respectively, thus demonstrating good wetting and adhesion at 900 °C with very little interfacial reactivity or interdiffusion. The thermomechanical stresses caused by the difference in the coefficient of thermal expansion (CTE) between the Hastelloy C22^® superalloy (≈15.3 × 10⁻⁶ K⁻¹) and its alumina counterpart (≈8 × 10⁻⁶ K⁻¹) were the key issues that had to be resolved to avoid failure in this joint. In this work, a circular configuration of the Hastelloy C22^®/alumina joint was specifically designed to produce a feedthrough for sodium-based liquid metal batteries operating at high temperatures (up to 600 °C). In this configuration, adhesion between the metal and ceramic components was enhanced after cooling by compressive forces created on the joined area due to the difference in CTE between the two materials. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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9 pages, 1530 KiB

Open AccessArticle

Effect of Post-Weld Heat Treatment on Microstructure and Hardness of Laser Beam Welded 17-4 PH Stainless Steel

by Lechosław Tuz, Łukasz Sokołowski and Sebastian Stano

Materials 2023, 16(4), 1334; https://doi.org/10.3390/ma16041334 - 04 Feb 2023

Cited by 6 | Viewed by 1910

Abstract

This article presents the results of research on the development of the technology of laser beam butt welding of 17-4 PH stainless steel sheets and the technology of post-weld heat treatment (PWHT). The developed technology allows for favorable conditions to be obtained and [...] Read more.

This article presents the results of research on the development of the technology of laser beam butt welding of 17-4 PH stainless steel sheets and the technology of post-weld heat treatment (PWHT). The developed technology allows for favorable conditions to be obtained and for the appropriate microstructure and hardness to exist in the weld area. Moreover, it enables the fulfillment of a number of specific requirements beyond the possibilities of manual welding and other methods. The tests performed include the analysis of the microstructure with the use of light microscopy (LM) for the materials after welding and PWHT. The applied PWHT showed changes in the microstructure and mechanical properties. In all weld areas the martensitic microstructure was observed. The homogeneity of the microstructure in the area of the welded joint after PWTH was revealed. In the as-welded condition and after the PWHT with aging at 481 °C, the hardness was 440 HV5, but after aging at 621 °C, it decreased to 330–340 HV5. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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16 pages, 3894 KiB

Open AccessArticle

Investigation of Welding Parameters of Dissimilar Weld of SS316 and ASTM A36 Joint Using a Grey-Based Taguchi Optimization Approach

by Diah Kusuma Pratiwi, Amir Arifin, Gunawan, Alim Mardhi and Afriansyah

J. Manuf. Mater. Process. 2023, 7(1), 39; https://doi.org/10.3390/jmmp7010039 - 02 Feb 2023

Cited by 9 | Viewed by 2294

Abstract

A grey-based Taguchi method was applied to investigate the optimal operating conditions in shielded metal arc welding (SMAW) to join SS316 and ASTM A36. This work aims to set optimal parameters for the mechanical properties of the weld joint. The effects of various [...] Read more.

A grey-based Taguchi method was applied to investigate the optimal operating conditions in shielded metal arc welding (SMAW) to join SS316 and ASTM A36. This work aims to set optimal parameters for the mechanical properties of the weld joint. The effects of various welding factors on electrode type, welding current, arc welding, and welding speed have to be characterized and optimized to achieve an optimum condition. An L9 orthogonal array was used to group the various components. The mechanical properties of a dissimilar weld joints were described through hardness, tensile and flexural strength tests. The optimum welding parameters were obtained simultaneously as an electrode type E309, a welding current of 100 A, an arc voltage of 14 V, and a welding speed of 4 cm/min, which predicted improve 23.0% in its performance. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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20 pages, 12744 KiB

Open AccessArticle

Mechanical Properties of Structural Components in Hastelloy X Joints Brazed with Ni-Pd-Cr-B-Si Alloy

by Michał Baranowski and Jacek Senkara

Materials 2023, 16(3), 1115; https://doi.org/10.3390/ma16031115 - 28 Jan 2023

Cited by 3 | Viewed by 1683

Abstract

The brazing of structural high-temperature-resistant nickel alloys is a predominant method in manufacturing jet engines in the aircraft industry. Ni-Cr-base brazing filler metals (BFMs) containing B and Si as the melting point depressants are used for this purpose. The presence of the latter [...] Read more.

The brazing of structural high-temperature-resistant nickel alloys is a predominant method in manufacturing jet engines in the aircraft industry. Ni-Cr-base brazing filler metals (BFMs) containing B and Si as the melting point depressants are used for this purpose. The presence of the latter can lead to the formation of brittle constituents in the joints, decreasing their strength, toughness and creep resistance. The structures of Hastelloy X nickel superalloy joints brazed with Palnicro 36M BFM are presented in this paper along with the mechanical properties of their particular phases as a function of brazing time. Indentation hardness, Martens hardness, reduced modulus and creep coefficient were measured using the instrumented indentation method. The elastic part of the indentation work was also calculated. Pd forms an unlimited solution with Ni, but its high content in BFM does not fundamentally change the general joint structure known from other Ni-superalloy–Ni-BFM systems. However, new Pd-containing phases are emerging. The hardest components were Ni-B and Cr-B boride phases and Pd-Ni-Si phase in MZ and the boundary of DAZ and BM. MZ reduces the plasticity of a joint to the highest extent. The hardness of particular parts in the joints and the elastic portion of the indentation work decreased with the increase in brazing time, while the reduced modulus of the indentation contact and indentation creep increased. The results of indentation creep measurements indicate that all structural components of the joints were less susceptible to creep than the parent material at room temperature. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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12 pages, 7076 KiB

Open AccessArticle

Influence of Long-Term Subcritical Annealing on the Unalloyed Steel Welded Joint Microstructure

by Dominika Fajt, Mariusz Maślak, Marek Stankiewicz, Paulina Zajdel and Krzysztof Pańcikiewicz

Materials 2023, 16(1), 304; https://doi.org/10.3390/ma16010304 - 28 Dec 2022

Cited by 1 | Viewed by 1359

Abstract

The article presents changes in the microstructure of hot-rolled unalloyed structural steel after the arc welding process and in the state after long-term exposure to 600 °C during operation. These studies enable a clear assessment of the effects of long-term exposure to elevated [...] Read more.

The article presents changes in the microstructure of hot-rolled unalloyed structural steel after the arc welding process and in the state after long-term exposure to 600 °C during operation. These studies enable a clear assessment of the effects of long-term exposure to elevated temperature relative to the as-welded condition, which has not been reported. The microstructure examination was carried out on welded joints in eight different zones of the joint. Studies have shown that the welding thermal cycle causes significant changes in the microstructure in the area of the base material heated above the A₁ temperature—the heat-affected zone (HAZ)—and in the weld area in the case of multi-pass welding. The long-term exposure of the subcritical temperature of 600 °C on the welded joint leads to the phenomenon of cementite spheroidization in the pearlite in all zones of the joint, while preserving the band structure of the steel after rolling and the structural structure. In the case of the weld, acicular and side-plate ferrite disappearance was observed. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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17 pages, 9967 KiB

Open AccessArticle

Microstructure and Mechanical Properties of Combined GTAW and SMAW Dissimilar Welded Joints between Inconel 718 and 304L Austenitic Stainless Steel

by Sachin Sirohi, Shailesh M. Pandey, Aleksandra Świerczyńska, Grzegorz Rogalski, Naveen Kumar, Michał Landowski, Dariusz Fydrych and Chandan Pandey

Metals 2023, 13(1), 14; https://doi.org/10.3390/met13010014 - 21 Dec 2022

Cited by 21 | Viewed by 2982

Abstract

A dissimilar welded joint of Inconel 718 and 304L austenitic stainless steel was prepared using a combined procedure with the gas tungsten arc welding and shielded metal arc welding processes by employing the Ni-based fillers: ERNiCr-3 and ENiCrFe-3. The welded joints were investigated [...] Read more.

A dissimilar welded joint of Inconel 718 and 304L austenitic stainless steel was prepared using a combined procedure with the gas tungsten arc welding and shielded metal arc welding processes by employing the Ni-based fillers: ERNiCr-3 and ENiCrFe-3. The welded joints were investigated for metallographic testing and mechanical properties, and a relationship was established between the microstructure and the resultant mechanical properties. Microstructural observation revealed the formation of the unmixed zone on the 304L SS side. The weld metal showed that the fully austenitic microstructure consisted of the Nb- and Ti-rich carbide phases along the inter-dendritic spaces. The tensile test results at room temperature showed the failure from the weld metal which might be due to alloying element segregation along the inter-dendritic spaces. However, a tensile test at 600 °C showed the failure from the 304L SS base metal with a tensile strength and % elongation value of 377 MPa and 24%, respectively. The hardness plot showed the average hardness value of the weld metal of 236 ± 5 HV, which was higher than the 304L SS BM (204 ± 4 HV) but lower than the IN718 BM (243 ± 5 HV). The impact toughness of the weld metal was 109 J, which was significantly lower than the base metals. The poor impact strength of the weld metal might be due to the evolution of the NbC phase along inter-dendritic spaces. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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14 pages, 4087 KiB

Open AccessArticle

New Pressure-Sensitive Acrylic Adhesives for Low Energy Substrates Prepared via UV-Induced Telomerization with a Fluorine-Based Telogen

by Agnieszka Kowalczyk, Agata Kraśkiewicz and Krzysztof Kowalczyk

Materials 2022, 15(23), 8667; https://doi.org/10.3390/ma15238667 - 05 Dec 2022

Viewed by 1388

Abstract

Novel pressure-sensitive adhesives (PSA) for low energy substrates were prepared by a solvent-free UV-initiated telomerization process using n-butyl acrylate, butyl methacrylate, and lauryl methacrylate (LMA), with trifluoroethanol (TFEtOH) as a telogen, and acylphosphine oxide (APO) as a radical photoinitiator. A crosslinking monomer (an [...] Read more.

Novel pressure-sensitive adhesives (PSA) for low energy substrates were prepared by a solvent-free UV-initiated telomerization process using n-butyl acrylate, butyl methacrylate, and lauryl methacrylate (LMA), with trifluoroethanol (TFEtOH) as a telogen, and acylphosphine oxide (APO) as a radical photoinitiator. A crosslinking monomer (an aliphatic urethane acrylate, L9033) and a radical UV-photoinitiator (α-hydroxyalkylphenone) were also tested as components of the adhesive compositions. The influence of LMA and TFEtOH on the UV-phototelomerization process kinetics and the physicochemical features of the obtained fluorotelomers, as well as the concentration of L9033 on the PSA adhesion to a polyethylene surface, were investigated. FT-IR results indicated that the fluorine groups were successfully introduced into the telomer structure. The highest adhesion relative to a polyethylene substrate (12.3 N/25 mm), and the highest hydrophobicity (with a contact angle of 95° for a water/PSA system) were observed for adhesives based on a telomer syrup containing 5 wt. parts of TFEtOH and 30 wt. parts of LMA (per 100 wt. parts of the monomer mixture). Additionally, it was revealed that a higher aliphatic urethane acrylate content and a higher UV dose increased the adhesion feature. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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28 pages, 7301 KiB

Open AccessArticle

Numerical Simulations Based on a Meshfree Method for Nickel-Steel Welded Joint Manufactured by Micro-Jet Cooling

by Anita Uściłowska, Bożena Szczucka-Lasota, Tomasz Węgrzyn, Tadeusz Szymczak, Bogusław Łazarz and Joanna Kamińska

Materials 2022, 15(23), 8579; https://doi.org/10.3390/ma15238579 - 01 Dec 2022

Cited by 3 | Viewed by 1260

Abstract

The article presents a numerical–experimental approach to the weldability and mechanical resistance of the joint of Alloy 59 (2.4605, nickel-chromium-molybdenum) and S355J2W (1.8965) structural steel manufactured by the MIG process with the use of micro-jet cooling. This research was considered because the standard [...] Read more.

The article presents a numerical–experimental approach to the weldability and mechanical resistance of the joint of Alloy 59 (2.4605, nickel-chromium-molybdenum) and S355J2W (1.8965) structural steel manufactured by the MIG process with the use of micro-jet cooling. This research was considered because the standard MIG process does not guarantee the procurement of a mixed hard-rusting structural steel superalloy weld of a repeatable and acceptable quality. Welds made through the classic MIG process express cracks that result from their unfavorable metallographic microstructure, while the joint supported by micro-jet cooling does not reflect any cracks and has a high strength with good flexibility. This was achieved by the application of helium for cooling. The joining technology was also considered in the numerical stage, represented by calculations in situ. For this purpose, the fundamental solution method (FSM) for the simulation of heat transfer during the process of welding with micro-jet cooling was implemented according to the initial boundary value problem (IBVP). The problem was solved employing the method of combining the finite difference method, Picard iterations, approximation by the radial basis function, and the fundamental solution method so as to solve the IVBP. The proposed method was validated by the data and results obtained during in situ experiments. The numerical approach enabled us to obtain variations in the temperature distribution values in HAZ with its different dimensional variants, ranging between 600 °C and 1400 °C. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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16 pages, 6508 KiB

Open AccessReview

Role of Crystallographic Orientation of β-Sn Grain on Electromigration Failures in Lead-Free Solder Joint: An Overview

by Muhammad Nasir Bashir, Sajid Ullah Butt, Muhammad Adil Mansoor, Niaz Bahadur Khan, Shahid Bashir, Yew Hoong Wong, Turki Alamro, Sayed Mohamed Eldin and Mohammed Jameel

Coatings 2022, 12(11), 1752; https://doi.org/10.3390/coatings12111752 - 15 Nov 2022

Cited by 4 | Viewed by 2128

Abstract

Due to the miniaturization of electronic devices, electromigration became one of the serious reliability issues in lead-free solder joints. The orientation of the β-Sn grain plays an important role in electromigration failures. Several studies have been carried out to investigate the effect of [...] Read more.

Due to the miniaturization of electronic devices, electromigration became one of the serious reliability issues in lead-free solder joints. The orientation of the β-Sn grain plays an important role in electromigration failures. Several studies have been carried out to investigate the effect of Sn grain orientation on electromigration. The efforts involve the influence of β-Sn grain orientation on the migration of Cu, Sn, and Ni atoms, on the morphology of the solder joint, and on the formation of Cu6Sn5 and (Cu, Ni)6Sn6 in the lead-free solder joint during electromigration. The current review provides a detailed review of past studies which were conducted to investigate the influence of β-Sn grain orientation on electromigration failures in lead-free solder joints. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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22 pages, 9196 KiB

Open AccessArticle

Hardox 450 Weld in Microstructural and Mechanical Approaches after Welding at Micro-Jet Cooling

by Abílio P. Silva, Tomasz Węgrzyn, Tadeusz Szymczak, Bożena Szczucka-Lasota and Bogusław Łazarz

Materials 2022, 15(20), 7118; https://doi.org/10.3390/ma15207118 - 13 Oct 2022

Cited by 2 | Viewed by 1709

Abstract

The demand for high-strength steel welds, as observed in civil and transport engineering, is related to a mass reduction in vehicles. Container-type trucks are examples of this kind of transport means because their boxes are able to be produced using Hardox grade steels. [...] Read more.

The demand for high-strength steel welds, as observed in civil and transport engineering, is related to a mass reduction in vehicles. Container-type trucks are examples of this kind of transport means because their boxes are able to be produced using Hardox grade steels. Therefore, this study reflects on the properties of welds in the MAG welding of Hardox 450, obtained through an innovative micro-jet cooling process with helium. This joining technology aims to reduce the formation of defects and to obtain a joint with very good assumed mechanical properties. Structural components of grade steel require welds with acceptable mechanical parameters with respect to operational loading conditions. That is, this study focuses on selecting welding parameters for the Hardox 450 steel and determining the weld quality with respect to microstructural observations and mechanical tests, such as the Charpy, tensile and fatigue tests. Weld fracturing under increasing monotonic force was examined and was strongly related to both stress components, i.e., axial and shear. The joint response under fatigue was expressed through differences in the fracture zones, i.e., at a stress value lower than the proportional limit, and weld degradation occurred in the shear and axial stress components. The data indicate that the hourglass specimen, with the weld in the centre zone of the measurement section, can be directly used to determine a weld response under cyclic loading. The impact test results showed attractive behaviour in the tested joint, as represented by 47 J at −20 °C. The recommended MAG welding parameters for Hardox 450 steel are low-oxygen when using an Ar + 18% CO₂ shielding mixture. The collected results can be directly used as a guide to weld thin-walled structures (6 mm) made of Hardox grade steel, while the data from mechanical tests can support the modelling, designing and manufacturing of components made from this kind of steel grade. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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21 pages, 9294 KiB

Open AccessArticle

Wire Arc Additive Manufactured Mild Steel and Austenitic Stainless Steel Components: Microstructure, Mechanical Properties and Residual Stresses

by Kasireddy Usha Rani, Rajiv Kumar, Manas M. Mahapatra, Rahul S. Mulik, Aleksandra Świerczyńska, Dariusz Fydrych and Chandan Pandey

Materials 2022, 15(20), 7094; https://doi.org/10.3390/ma15207094 - 12 Oct 2022

Cited by 17 | Viewed by 2673

Abstract

Wire arc additive manufacturing (WAAM) is an additive manufacturing process based on the arc welding process in which wire is melted by an electric arc and deposited layer by layer. Due to the cost and rate benefits over powder-based additive manufacturing technologies and [...] Read more.

Wire arc additive manufacturing (WAAM) is an additive manufacturing process based on the arc welding process in which wire is melted by an electric arc and deposited layer by layer. Due to the cost and rate benefits over powder-based additive manufacturing technologies and other alternative heat sources such as laser and electron beams, the process is currently receiving much attention in the industrial production sector. The gas metal arc welded (GMAW) based WAAM process provides a higher deposition rate than other methods, making it suitable for additive manufacturing. The fabrication of mild steel (G3Si1), austenitic stainless steel (SS304), and a bimetallic sample of both materials were completed successfully using the GMAW based WAAM process. The microstructure characterization of the developed sample was conducted using optical and scanning electron microscopes. The interface reveals two discrete zones of mild steel and SS304 deposits without any weld defects. The hardness profile indicates a drastic increase in hardness near the interface, which is attributed to chromium migration from the SS304. The toughness of the sample was tested based on the Charpy Impact (ASTM D6110) test. The test reveals isotropy in both directions. The tensile strength of samples deposited by the WAAM technique measured slightly higher than the standard values of weld filament. The deep hole drilling (DHD) method was used to measure the residual stresses, and it was determined that the stresses are compressive in the mild steel portion and tensile in austenitic stainless steel portion, and that they vary throughout the thickness due to variation in the cooling rate at the inner and outer surfaces. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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15 pages, 6693 KiB

Open AccessArticle

Effect of Welding Parameters on Mechanical Properties and Microstructure of Friction Stir Welded AA7075-T651 Aluminum Alloy Butt Joints

by Robert Kosturek, Janusz Torzewski, Marcin Wachowski and Lucjan Śnieżek

Materials 2022, 15(17), 5950; https://doi.org/10.3390/ma15175950 - 28 Aug 2022

Cited by 5 | Viewed by 1724

Abstract

The aim of this study was to examine the mechanical properties of 5-mm-thick AA7075-T651 alloy using three different welding velocities, 50, 75 and 100 mm/min, and four various sets of tool rotation speeds: 400, 600, 800 and 1000 rpm. All obtained joints were [...] Read more.

The aim of this study was to examine the mechanical properties of 5-mm-thick AA7075-T651 alloy using three different welding velocities, 50, 75 and 100 mm/min, and four various sets of tool rotation speeds: 400, 600, 800 and 1000 rpm. All obtained joints were defect-free. In all cases, the values of UTS exceeded 400 MPa, corresponding to 68.5% minimum joint efficiency. The highest value of 447.7 MPa (76.7% joint efficiency) was reported for the joint produced via 400 rpm tool rotation speed and 100 mm/min welding velocity. The SZ microstructure of the strongest joint was characterized by a 5.2 ± 1.7 μm grain size and microhardness of approximately 145 HV0.1. The TMAZ/HAZ interface was identified as the low-hardness zone (105–115 HV0.1, depending on parameters), where the failure of the tensile samples takes place. The fracture mechanism is dominated by a transgranular ductile rupture with microvoid coalescence. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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10 pages, 5597 KiB

Open AccessArticle

Joining of SiC Ceramic by Si–C Reaction Bonding Using Organic Resin as Carbon Precursor

by Xishi Wu, Qing Huang, Yunzhou Zhu and Zhengren Huang

Materials 2022, 15(12), 4242; https://doi.org/10.3390/ma15124242 - 15 Jun 2022

Cited by 5 | Viewed by 2278

Abstract

In this study, the joining of silicon carbide (SiC) ceramics was achieved via a Si–C reaction bonding method using the phenolic resin (PF)–MgCl₂ system as the carbon precursor. Specifically, by adding MgCl₂ to the phenolic resin mixture, the average pore size [...] Read more.

In this study, the joining of silicon carbide (SiC) ceramics was achieved via a Si–C reaction bonding method using the phenolic resin (PF)–MgCl₂ system as the carbon precursor. Specifically, by adding MgCl₂ to the phenolic resin mixture, the average pore size of the product of carbonization of the PF resin mixture increased from 14 ± 5 nm to 524 ± 21 nm, which was beneficial for the infiltration of molten silicon at high temperature. The microstructure of the joined specimens and the effect of the inert filler on the joint strength were investigated. It was demonstrated that SiC–SiC joints with strong interfacial bonding and high flexural strength could be obtained by the Si–C reaction bonding method using a phenol formaldehyde resin/alcohol sol-gel system as the carbon precursor. The flexural strength of the joined specimens reached the highest value, i.e., 308 ± 27 MPa when the solid loading of the inert filler was 26%. Overall, stable joining of silicon carbide ceramics was achieved by the proposed method, which has significance for realizing the preparation of complex-shaped or large silicon carbide ceramic parts. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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26 pages, 25669 KiB

Open AccessArticle

Influence of PWHT Parameters on the Mechanical Properties and Microstructural Behavior of Multi-Pass GTAW Joints of P92 Steel

by Sachin Sirohi, Amit Kumar, Shiva Soni, Gaurav Dak, Sanjeev Kumar, Aleksandra Świerczyńska, Grzegorz Rogalski, Dariusz Fydrych and Chandan Pandey

Materials 2022, 15(12), 4045; https://doi.org/10.3390/ma15124045 - 07 Jun 2022

Cited by 11 | Viewed by 2241

Abstract

The 9% Cr steels were developed for ultra-supercritical (USC) power plants to meet the requirements of high operating temperature and pressure. These steels are produced to operate at high temperatures where impact toughness is not a concern; however, it becomes important for the [...] Read more.

The 9% Cr steels were developed for ultra-supercritical (USC) power plants to meet the requirements of high operating temperature and pressure. These steels are produced to operate at high temperatures where impact toughness is not a concern; however, it becomes important for the welded joints to have good impact toughness at room temperature for manufacturing. The present work investigates the effect of the post-weld heat treatment (PWHT) parameters, i.e., temperature and time, on the impact toughness of multi-pass gas tungsten arc welded (GTAW) joints of ferritic/martensitic grade P92 steel. The microstructural evolution in welded joints given varying post-weld temperatures and times was studied. The lath martensitic structure of the weld metal for the as-welded joints resulted in high hardness and low impact toughness. The weld fusion zone toughness was 12 J, which was lower than the minimum specified values of 41 J (ASME standards) and 47 J (EN ISO 3580:2017). The PWHT temperature and time were found to have a significant effect on the impact toughness of the weld metal. A drastic increase in the impact toughness of the weld metal was noticed, which was attributed to lath break-up, reduction in dislocation density and reduction in solid solution hardening. The maximum impact toughness of 124 J was measured for PWHT temperature and time of 760 °C and 120 min, respectively. The effect of PWHT parameters on tensile strength was also investigated, and test results showed that the joint was safe for USC boiler application as it failed from the region of the P92 base metal. The variation in microstructural evolution along the weldments resulted in hardness variation. PWHT led to homogeneity in microstructure and, ultimately, reduction in hardness value. According to the study, the optimum temperature and time for PWHT of a GTAW joint of P92 steel were found to be 760 °C and 120 min, respectively. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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13 pages, 16492 KiB

Open AccessArticle

Liquation Cracking Susceptibility and Mechanical Properties of 7075 Aluminum Alloy GTAW Joints

by Zhuoxin Li, Yulin Zhang, Hong Li, Yipeng Wang, Lijuan Wang and Yu Zhang

Materials 2022, 15(10), 3651; https://doi.org/10.3390/ma15103651 - 20 May 2022

Cited by 3 | Viewed by 1790

Abstract

In this work, aluminum alloy 7075-T651 was welded by using customized Al-Cu-Si and Al-Cu-Mg-Zn filler wire during gas tungsten arc welding. The liquation cracking susceptibility of the joints was tested under a circular-patch welding experiment. Besides, the temperature vs. solid fraction curves ( [...] Read more.

In this work, aluminum alloy 7075-T651 was welded by using customized Al-Cu-Si and Al-Cu-Mg-Zn filler wire during gas tungsten arc welding. The liquation cracking susceptibility of the joints was tested under a circular-patch welding experiment. Besides, the temperature vs. solid fraction curves (T-f_S) was calculated for different samples to reveal the formation mechanism of liquation cracking. The joint was susceptible to liquation cracking if (f_S)_weld > (f_S)_workpiece during the cooling stage. The results of the circular-patch welding experiment show that the liquation cracking susceptibility of the joint by using ER5356, Al-Cu_1.5-Si_4.5, Al-Cu_3.0-Si_2.5, Al-Cu_4.5-Si_1.5, Al-Cu_2.3-Mg_2.3-Zn_6.6 and Al-Cu_2.2-Mg_2.0-Zn_7.8 filler metal is 22.8%, 8.3%, 2.8%, 2.8%, 3.3% and 1.4%, respectively. The mechanical test shows that the data dispersion of the 7075 gas tungsten arc welding joint can be decreased by eliminating the liquation crack. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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15 pages, 5618 KiB

Open AccessArticle

Effects of Underwater Friction Stir Welding Heat Generation on Residual Stress of AA6068-T6 Aluminum Alloy

by Hassanein I. Khalaf, Raheem Al-Sabur, Mahmoud E. Abdullah, Andrzej Kubit and Hamed Aghajani Derazkola

Materials 2022, 15(6), 2223; https://doi.org/10.3390/ma15062223 - 17 Mar 2022

Cited by 33 | Viewed by 2647

Abstract

This article aims to study water-cooling effects on residual stress friction stir welding (FSW) of AA6068-T6 aluminum alloy. For this reason, the FSW and submerged FSW processes are simulated by computational fluid dynamic (CFD) method to study heat generation. The increment hole drilling [...] Read more.

This article aims to study water-cooling effects on residual stress friction stir welding (FSW) of AA6068-T6 aluminum alloy. For this reason, the FSW and submerged FSW processes are simulated by computational fluid dynamic (CFD) method to study heat generation. The increment hole drilling technique was used to measure the residual stress of welded samples. The simulation results show that materials softening during the FSW process are more than submerged. This phenomenon caused the residual stress of the joint line in the submerged case to be lower than in the regular FSW joint. On the other hand, the results revealed that the maximum residual stresses in both cases are below the yielding strength of the AA6068-T6 aluminum alloy. The results indicated that the residual stress along the longitudinal direction of the joint line is much larger than the transverse direction in both samples. Full article

(This article belongs to the Topic Welding and Joining of Materials in Off-Shore and Energy Industry)

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