Research

Jump to: Review

15 pages, 14228 KiB

Open AccessArticle

Numerical Study of Laser Welding of 270 μm Thick Silicon–Steel Sheets for Electrical Motors

by Dae Gune Jung, Ji Young Park, Choong Mo Ryu, Jong Jin Hwang and Seung Jae Moon

Metals 2024, 14(1), 24; https://doi.org/10.3390/met14010024 - 25 Dec 2023

Viewed by 702

In this study, the shape of laser welding parts required to develop a welding automation system was analyzed to improve the production process of thin-plate silicon–steel. During laser welding, a welding defect occurs in the welding area, resulting in beads. This can be [...] Read more.

In this study, the shape of laser welding parts required to develop a welding automation system was analyzed to improve the production process of thin-plate silicon–steel. During laser welding, a welding defect occurs in the welding area, resulting in beads. This can be measured and analyzed through computational fluid dynamics. When welding thin plates with a laser, precise parameter settings are required to reduce bead height and side effects to improve weld quality. Twelve simulation cases with different laser powers and scan speeds were carried out to compare bead heights. We discussed ways to improve the productivity of electrical steel sheets by applying data collected through simulations of a laser welding automation system. Full article

(This article belongs to the Special Issue Feature Papers in Welding & Joining)

► Show Figures

Figure 1

30 pages, 27454 KiB

Open AccessArticle

Improving the Weld Heat-Affected-Zone (HAZ) Toughness of High-Strength Thick-Walled Line Pipes

by Yan Ma, Lihong Su, Chen Shen, Leigh Fletcher, Huijun Li, Leilei Sun, Lei Zheng and Chuanguo Zhang

Metals 2023, 13(12), 2018; https://doi.org/10.3390/met13122018 - 16 Dec 2023

Viewed by 1166

Abstract

The low-temperature fracture toughness of double-V weld seams is a well-known challenge due to the essential increased heat input for heavy-wall pipelines. A thorough investigation was conducted to explore the impact of the heat input on the grain size and precipitate coarsening, correlating [...] Read more.

The low-temperature fracture toughness of double-V weld seams is a well-known challenge due to the essential increased heat input for heavy-wall pipelines. A thorough investigation was conducted to explore the impact of the heat input on the grain size and precipitate coarsening, correlating the microstructure with the heat-affected-zone (HAZ) toughness. The results indicated that the actual weldments showed a toughness transition zone at −20 °C, with considerable scattering in Charpy V-notch (CVN) tests. Gleeble thermal simulations confirmed the decreased toughness of the coarse-grained HAZ (CGHAZ) with increasing heat input and prior austenite grain size (PAGS). A specially designed thermal treatment demonstrated its potential for enhancing the toughness of the CGHAZ, with the recommended thermal cycle involving peak temperatures of 700 and 800 °C, holding for 1 s, and rapid cooling. The toughness of the intercritically reheated CGHAZ (ICCGHAZ) improved with higher intercritical reheating temperatures and the removal of necklace-type M–A constituents along the PAG. Despite various thermal treatments, no significant improvements were observed in the toughness of the ICCGHAZ. Future work was suggested for optimising the use of tack welds to reduce the effective heat input (HI) associated with double-sided submerged arc welding (SAW). Full article

(This article belongs to the Special Issue Feature Papers in Welding & Joining)

► Show Figures

Figure 1

16 pages, 5643 KiB

Open AccessArticle

Modal Analysis of Ultrasonic Spot Welding for Lightweight Metals Joining

by Hui Huang, Jian Chen, Zhili Feng and Xin Sun

Metals 2023, 13(10), 1735; https://doi.org/10.3390/met13101735 - 13 Oct 2023

Viewed by 912

Abstract

Ultrasonic spot welding (USW) represents one of the unique solid-state joining methods for lightweight materials such as magnesium alloy and aluminum alloy. However, the sonotrode vibration may have a detrimental impact on the sheet material and the existing welds, depending on the component [...] Read more.

Ultrasonic spot welding (USW) represents one of the unique solid-state joining methods for lightweight materials such as magnesium alloy and aluminum alloy. However, the sonotrode vibration may have a detrimental impact on the sheet material and the existing welds, depending on the component geometry and vibration frequency. In this study, a modal analysis tool based on steady-state dynamics was developed for ultrasonic spot welding which features a cyclic load applied to the sheets during the joining process. Through predicting relative motion and shear stress at the faying surfaces, coupon geometry and weld spacing are identified as two major factors that affect the welding reliability and joint quality in USW. The model was validated via welding experiments on aluminum alloy and magnesium alloy and relevant characterization of temperature distribution, joint strength as well as fracture location. Full article

(This article belongs to the Special Issue Feature Papers in Welding & Joining)

► Show Figures

Figure 1

12 pages, 1965 KiB

Open AccessArticle

Intelligent and Adaptive System for Welding Process Automation in T-Shaped Joints

by Eider Aldalur, Alfredo Suárez, David Curiel, Fernando Veiga and Pedro Villanueva

Metals 2023, 13(9), 1532; https://doi.org/10.3390/met13091532 - 29 Aug 2023

Cited by 1 | Viewed by 1182

Abstract

The automation of welding processes requires the use of automated systems and equipment, in many cases industrial robotic systems, to carry out welding processes that previously required human intervention. Automation in the industry offers numerous advantages, such as increased efficiency and productivity, cost [...] Read more.

The automation of welding processes requires the use of automated systems and equipment, in many cases industrial robotic systems, to carry out welding processes that previously required human intervention. Automation in the industry offers numerous advantages, such as increased efficiency and productivity, cost reduction, improved product quality, increased flexibility and safety, and greater adaptability of companies to market changes. The field of welding automation is currently undergoing a period of profound change due to a combination of technological, regulatory, and economic factors worldwide. Nowadays, the most relevant aspect of the welding industry is meeting customer requirements by satisfying their needs. To achieve this, the automation of the welding process through sensors and control algorithms ensures the quality of the parts and prevents errors, such as porosity, unfused areas, deformations, and excessive heat. This paper proposes an intelligent and adaptive system based on the measurement of welding joints using laser scanning and the subsequent analysis of the obtained point cloud to adapt welding trajectories. This study focuses on the optimization of T-joints under specific welding conditions and is intended as an initial implementation of the algorithm, thus establishing a basis to be worked on further for a broader welding application. Full article

(This article belongs to the Special Issue Feature Papers in Welding & Joining)

► Show Figures

Figure 1

21 pages, 7113 KiB

Open AccessArticle

Features of Structure and Properties of Lap-Welded Joints of Aluminum Alloy Al–4Cu–1Mg with Titanium Alloy Ti–6Al–4V, Obtained by Friction Stir Welding

by Alexey Ivanov, Andrey Chumaevskii, Alihan Amirov, Veronika Utyaganova, Nikolay Savchenko, Valery Rubtsov and Sergei Tarasov

Metals 2023, 13(8), 1385; https://doi.org/10.3390/met13081385 - 01 Aug 2023

Cited by 2 | Viewed by 879

Abstract

Lap-welded joints between Ti–6Al–4V and Al–4Cu–1Mg were obtained using water-cooling-bath friction stir welding at different FSW tool rotation rates. The increase in the tool rotation rate from 350 to 375 RPM leads to better plasticization of the titanium alloy, elimination of stir zone [...] Read more.

Lap-welded joints between Ti–6Al–4V and Al–4Cu–1Mg were obtained using water-cooling-bath friction stir welding at different FSW tool rotation rates. The increase in the tool rotation rate from 350 to 375 RPM leads to better plasticization of the titanium alloy, elimination of stir zone defects, better interlocking and bonding with the aluminum alloy as well as the formation of intermetallic Al–Ti compounds (IMC), preferentially of the Al₃Ti type. Shear-loading testing showed the best result was at the level of 3000 N with 2 mm of displacement. Increasing the FSW tool rotation rate to 400 and 450 RPM resulted in the formation of more IMCs, which had a detrimental effect on both maximum load and displacement achieved in the shear tests. Full article

(This article belongs to the Special Issue Feature Papers in Welding & Joining)

► Show Figures

Figure 1

12 pages, 4879 KiB

Open AccessArticle

Friction Welding of Polycarbonate Plate and Aluminum Foam Fabricated by Precursor Foaming Process

by Yoshihiko Hangai, Yuta Yamamoto, Yu Goto, Kenji Okada and Nobuhiro Yoshikawa

Metals 2023, 13(8), 1366; https://doi.org/10.3390/met13081366 - 29 Jul 2023

Cited by 2 | Viewed by 1048

Abstract

Aluminum foam is expected to be one of the candidates for lightweight materials for structural components as it is lightweight and has excellent shock absorption and sound absorption properties. However, aluminum foam has low tensile and flexural strength due to its thin cell [...] Read more.

Aluminum foam is expected to be one of the candidates for lightweight materials for structural components as it is lightweight and has excellent shock absorption and sound absorption properties. However, aluminum foam has low tensile and flexural strength due to its thin cell walls. Therefore, aluminum foam is used by combining with dense materials. In particular, with the recent trend toward multi-materials, research on the combination with lightweight resins is expected. In this study, we attempted to join aluminum foam fabricated by the precursor method to a thermoplastic resin polycarbonate (PCTA) plate by friction welding. It was found that the aluminum foam and PCTA plate can be joined in about 1 min by friction welding, by rotating the aluminum foam at 2000 rpm and pressing 1 mm into the PCTA plate. In addition, in the friction welding of aluminum foam and PCTA plate, it was found that the pores of the aluminum foam were maintained without being collapsed. The anchoring effect is presumably caused by the penetration of PCTA softened by the frictional heat generated by the friction welding into the pores. Furthermore, tensile tests of the joined samples showed that fracture occurred either at the joining interface or at the base material of the aluminum foam, and that the joining strength was equivalent to the tensile strength of the aluminum foam itself. Full article

(This article belongs to the Special Issue Feature Papers in Welding & Joining)

► Show Figures

Figure 1

11 pages, 2672 KiB

Open AccessArticle

Investigation of the Interfacial Reactions between the CoCuFeNi High Entropy Alloy and Sn Solder

by Tzu-Yang Chiang, Yong-Chi Chang, Chao-Hong Wang, Andromeda Dwi Laksono and Yee-Wen Yen

Metals 2023, 13(4), 710; https://doi.org/10.3390/met13040710 - 05 Apr 2023

Cited by 1 | Viewed by 1165

Abstract

The CoCuFeNi high entropy alloy (HEA) has excellent electrical, thermal, and mechanical properties. In electronic packaging technology, Sn is the major element of lead-free solders. In this study, we used the CoCuFeNi HEA as the substrate and Sn as the solder and investigated [...] Read more.

The CoCuFeNi high entropy alloy (HEA) has excellent electrical, thermal, and mechanical properties. In electronic packaging technology, Sn is the major element of lead-free solders. In this study, we used the CoCuFeNi HEA as the substrate and Sn as the solder and investigated the liquid/solid interfacial reactions of the Sn/CoCuFeNi system at 300, 375, and 450 °C for 30, 60, 100, 150, 360, and 480 min. The results indicated that the (Fe, Co)Sn₂ phase was formed in the Sn/CoCuFeNi couples for all various reaction temperatures and at different durations. Additionally, the (Co, Ni)Sn₂ phase was precipitated at the solder side and near the (Fe, Co)Sn₂ phase when the reaction time increased. The thickness of the (Fe, Co)Sn₂ phase increased with the increase in reaction temperature and time, and it was proportional to the square root of the reaction time. Overall, our results showed that the growth mechanism of the (Fe, Co)Sn₂ phase was diffusion-controlled in the Sn/CoCuFeNi couples. Full article

(This article belongs to the Special Issue Feature Papers in Welding & Joining)

► Show Figures

Figure 1

17 pages, 8475 KiB

Open AccessArticle

Research on Arc Morphology and Keyhole Behavior of Molten Pool in Magnetically Controlled Plasma-GMAW Welding

by Xinglin Miao, Hongtao Zhang, Fuchen Ge, Zhenyu He, Jianguo Gao and Zhaofang Su

Metals 2023, 13(1), 148; https://doi.org/10.3390/met13010148 - 11 Jan 2023

Cited by 3 | Viewed by 1094

Abstract

In the magnetically controlled Plasma-GMAW welding process, the composite arc forms a keyhole in the workpiece to be welded. In order to explore the effect of process parameters on arc coupling, weld pool and keyhole, and the behavior characteristics of keyhole, the arc [...] Read more.

In the magnetically controlled Plasma-GMAW welding process, the composite arc forms a keyhole in the workpiece to be welded. In order to explore the effect of process parameters on arc coupling, weld pool and keyhole, and the behavior characteristics of keyhole, the arc behavior and side weld pool information were collected using a welding arc acquisition system and a high-speed camera during bead-on-plate welding. The arc image is processed by pseudo-color enhancement technology, and the collected molten pool information is analyzed by boundary extraction algorithm and coordinate conversion algorithm, and the molten pool boundary and keyhole entrance width are obtained. It is found that the coupling degree of the two arcs increases with the increase in plasma current, GMAW current and magnetic field intensity. With the increase in plasma current, the size of keyhole inlet increases; with the increase of GMAW current, the size of keyhole inlet decreases, and the wave crest increases. With the increase of magnetic field intensity, the intensity of metal oscillation between the two arcs increases, and so does the wave crest. Full article

(This article belongs to the Special Issue Feature Papers in Welding & Joining)

► Show Figures

Figure 1

19 pages, 5048 KiB

Open AccessArticle

Investigation of Dissimilar Resistance Spot Welding Process of AISI 304 and AISI 1060 Steels with TLBO-ANFIS and Sensitivity Analysis

by Mehdi Safari, Ricardo J. Alves de Sousa, Amir Hossein Rabiee and Vahid Tahmasbi

Metals 2021, 11(8), 1324; https://doi.org/10.3390/met11081324 - 21 Aug 2021

Cited by 7 | Viewed by 1773

Abstract

In this work, the process of dissimilar resistance spot welding (RSW) for AISI 304 and AISI 1060 steel sheets is experimentally investigated. The effects of the main process parameters such as welding current, electrode force, welding cycle, and cooling cycle on the tensile-shear [...] Read more.

In this work, the process of dissimilar resistance spot welding (RSW) for AISI 304 and AISI 1060 steel sheets is experimentally investigated. The effects of the main process parameters such as welding current, electrode force, welding cycle, and cooling cycle on the tensile-shear strength (TSS) of dissimilar RSW joints are studied. To this aim, using a central composite experimental design based on response surface methodology (RSM), the experimental tests were performed. Furthermore, from the test results, an adaptive neuro-fuzzy inference system (ANFIS) was developed to model and estimate the TSS. The optimal parameters of the ANFIS system were obtained using a teaching-learning-based optimization (TLBO) algorithm. In order to model the process behavior, the results of experiments were used for the training (70% of the data) and testing (30% of the data) of the adaptive inference system. The accuracy of the obtained model was investigated via different plots and statistical criteria including root mean square error, correlation coefficient, and mean absolute percentage error. The findings show that the ANFIS network successfully predicts the TSS. In addition, the network error in estimating the TSS in the training and test section is equal to 0.08% and 5.87%, respectively. After modeling with TLBO-ANFIS, the effect of each input parameter on TSS of the dissimilar joints is quantitatively measured using the Sobol sensitivity analysis method. The results show that increasing in welding current and welding cycle leads to an increase in the TSS of joints. It is concluded that TSS decreases with increases in the electrode force and cooling cycle. Full article

(This article belongs to the Special Issue Feature Papers in Welding & Joining)

► Show Figures

Figure 1

Review

Jump to: Research

37 pages, 9344 KiB

Open AccessReview

Wire-Feed Electron Beam Additive Manufacturing: A Review

by Ksenia Osipovich, Kirill Kalashnikov, Andrey Chumaevskii, Denis Gurianov, Tatiana Kalashnikova, Andrey Vorontsov, Anna Zykova, Veronika Utyaganova, Aleksandr Panfilov, Aleksandra Nikolaeva, Artem Dobrovolskii, Valery Rubtsov and Engeny Kolubaev

Metals 2023, 13(2), 279; https://doi.org/10.3390/met13020279 - 30 Jan 2023

Cited by 17 | Viewed by 3786

Abstract

The work is devoted to a review of modern achievements in the field of wire-feed electron beam additive manufacturing. The features of structure formation in aluminum, copper, titanium, nickel-based alloys, and steels during 3D printing are shown. Aspects of directional solidification during the [...] Read more.

The work is devoted to a review of modern achievements in the field of wire-feed electron beam additive manufacturing. The features of structure formation in aluminum, copper, titanium, nickel-based alloys, and steels during 3D printing are shown. Aspects of directional solidification during the production of components from various metals and alloys are considered. The prospects for obtaining composite and functionally graded materials based on various metals and alloys using wire-feed electron beam additive manufacturing are determined. The regularities of the structure modification and hardening of additively manufactured materials by the method of friction stir processing were considered. The main purpose of the review is to present additive manufacturing methods, the main focus being on the wire-feed electron beam additive manufacturing of metal alloys. Full article

(This article belongs to the Special Issue Feature Papers in Welding & Joining)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Feature Papers in Welding & Joining

Share This Special Issue

Special Issue Editor

Special Issue Information

Keywords

Published Papers (10 papers)

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI