Article
Materials Science, Multidisciplinary
Mohamed Saleh, Yoshiaki Morisada, Kohsaku Ushioda, Hidetoshi Fujii
Summary: In this study, dissimilar friction stir welding of mild steel and A7075 aluminum alloy was conducted. It was found that the higher the welding speed, the lower the maximum temperature during the joining process. Conducting the joining process at a high welding speed also increased the cooling rate, which effectively eliminated thermal residual stresses and suppressed interfacial intermetallic compounds growth. As a result, joints with 100% joint efficiency and steel base metal fracture were obtained at the welding speeds of 300 and 400 mm/min.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Yu Chen, Fenghe Zhang
Summary: In this study, dissimilar AA7075/Q235 steel joints were successfully fabricated via friction stir welding (FSW). The macro- and microstructures of the FSW joints varied depending on the welding heat input. Both the thickness of intermetallic compound (IMC) layers and the size of steel fragments played a role in controlling the FSW quality. However, the brittle failure of the FSW joints limited their application.
Review
Engineering, Mechanical
Armenio N. Correia, Daniel F. O. Braga, Pedro M. G. P. Moreira, Virginia Infante
Summary: Fuel economy is a central aspect in the industrial development of transportation means, with lightweight and multipurpose dissimilar structures playing a key role in innovation. Technologies like Friction Stir Welding are crucial in joining different materials, contributing to fuel consumption efficiency.
ENGINEERING FAILURE ANALYSIS
(2021)
Article
Engineering, Manufacturing
Surendra Kumar Lader, Mayuri Baruah, Raj Ballav
Summary: This research investigates the feasibility of aluminum and brass joints prepared in underwater friction stir welding (UFSW) at different values of plunge depth and rotational speed. The results show that compared to welding in the air (AFSW), welding in water significantly reduces weld defects such as cracks, tunnels, and voids. The lower welding temperature in UFSW reduces the formation of thick inter-metallic compounds (IMCs) and results in finer grains in the weld zone due to faster cooling rates.
JOURNAL OF MANUFACTURING PROCESSES
(2023)
Article
Materials Science, Multidisciplinary
Yue Yang, Zhen Luo, Yuanbo Bi, Yixuan Zhang
Summary: In order to achieve lightweight vehicles and energy-saving, the joining of dissimilar materials, specifically aluminum alloy and steel, has received increasing attention in car body structure. In this study, 6061 aluminum alloy and DP780 steel sheet were joined using resistance element welding (REW) technique with a flat Q235 rivet. The intermetallic compounds (IMCs) in the welded joints were analyzed using various characterization techniques, revealing the presence of Fe2Al5 and Fe4Al13 on the steel and aluminum sides, respectively.
MATERIALS CHARACTERIZATION
(2023)
Article
Engineering, Manufacturing
Jian Liu, Biao Cao, Jingwei Yang
Summary: This study systematically investigated the microstructure and intermetallic compounds of Cu/Al joints produced by high power ultrasonic welding (HUSW). The research found that the welding time had little effect on the grain morphology and size of pure copper, but had a significant impact on the aluminum alloy. Moreover, the texture characteristics of copper and aluminum alloy also changed during the welding process.
JOURNAL OF MANUFACTURING PROCESSES
(2022)
Article
Materials Science, Multidisciplinary
Narayanan Murali, Yitian Chi, Xiaochun Li
Summary: Nano-treatment shows great potential in enabling significant metallurgical capabilities in fusion welding dissimilar combinations of high-strength aluminum alloys, successfully addressing solidification defects and difficulties in heat treating, while promoting a significant natural aging response in the joint.
Article
Materials Science, Multidisciplinary
Mingfeng Li, Shanglu Yang, Yanjun Wang, Wu Tao
Summary: Reliably welding aluminum to steel is crucial in the automotive industry to achieve lightweight body structures. The proposed resistance spot welding process successfully joins AA6016 aluminum alloy and press hardened steel, forming an effective joint between the two materials.
Article
Nanoscience & Nanotechnology
Pai Peng, Kuaishe Wang, Wen Wang, Tao Yang, Qiang Liu, Ting Zhang, Shengyi Zhang, Jun Cai, Ke Qiao, Liqiang Wang, Hongduo Wang, Jian Liu
Summary: This study investigated the formation mechanism of intermetallic compounds (IMCs) and their effects on joint strength in dissimilar friction stir lap welding (FSLW) joints of AZ31 Mg alloys and Al-Zn-Cu-Mg alloys. New phases of Al12Mg17, Al3Mg2, MgZn2, and Al2Cu were found at the welding interface, with IMC formation sequence of Al12Mg17, Al3Mg2, MgZn2, and Al2Cu. During shearing deformation, cracks initiated at the hook zone in the retreading side and propagated along the welding interface where IMCs aggregate and strain concentrates. Small lattice mismatch between IMCs and matrix improved interfacial bonding strength.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
Kiyoaki T. Suzuki, Shun Omura, Shun Tokita, Yutaka S. Sato, Yujiro Tatsumi
Summary: In this study, an aluminum alloy sheet was successfully welded to a nickel-plated iron sheet using a silicon-containing aluminum filler by gas tungsten arc welding. The joint strength of the aluminum/iron interface was improved by the simultaneous addition of silicon and nickel, which resulted in a reduction in the intermetallic compound layer thickness and the refinement of its grains. The addition of silicon alone reduced the thickness of the intermetallic compound layer, while the addition of nickel further refined its grains. The combination of silicon and nickel showed the most effective improvement in joint strength.
MATERIALS & DESIGN
(2023)
Article
Materials Science, Multidisciplinary
Yue Yang, Yang Li, Jing Bi, Hanwei Liu, Sansan Ao, Zhen Luo
Summary: This study investigated the joining of AA2195-T8 aluminum-lithium and 5A06 aluminum alloys using resistance spot welding process. The results showed that the welded joints had lower microhardness and exhibited ductile-brittle hybrid fracture.
MATERIALS CHARACTERIZATION
(2022)
Article
Nanoscience & Nanotechnology
Nikhil Gotawala, Amber Shrivastava
Summary: The study analyzed the impact of variations in IMC thickness and microstructure at interface on the mechanical properties of RFW joints of Al6061 and mild steel. Different parameter combinations resulted in different effects, significantly influencing the tensile strength of the joints.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Engineering, Industrial
Pai Peng, Wen Wang, Ting Zhang, Qiang Liu, Xiaohu Guan, Ke Qiao, Jun Cai, Kuaishe Wang
Summary: In this study, the addition of Cu and Ni interlayer metals was found to reduce the content of intermetallic compounds in dissimilar joints of Mg and Al alloys, improving the mechanical properties. The interlayer metals effectively inhibited the formation of Mg-Al phase, leading to improved shear properties in the joints.
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY
(2022)
Article
Engineering, Mechanical
Anton Evdokimov, Nikolay Doynov, Ralf Ossenbrink, Aleksei Obrosov, Sabine Weiss, Vesselin Michailov
Summary: A numerical model was developed to compute distortions in laser-welded dissimilar overlap joints, considering properties of mixed steel-aluminum weld metal. Experimental results showed that the developed weld material model significantly improves the accuracy of thermomechanical simulations, with good agreement between computed and measured data.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Review
Engineering, Industrial
Jin Yang, J. P. Oliveira, Yulong Li, Caiwang Tan, Chenkai Gao, Yixuan Zhao, Zhishui Yu
Summary: The use of multi-material structures is an effective solution to reduce weight and emissions in the automotive industry. However, joining aluminum alloys to steels is challenging due to their mismatched properties. Laser-based processes have been explored to overcome this issue and this review examines the recent achievements and progress in this field, evaluating factors such as joining conditions, filler materials, microstructure, and mechanical properties.
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY
(2022)
Article
Automation & Control Systems
Niklas Gerdes, Christian Hoff, Jorg Hermsdorf, Stefan Kaierle, Ludger Overmeyer
Summary: This article discusses the relevance of in situ quality assurance in metal additive manufacturing for cost-efficient product qualification, presenting an approach for monitoring the LPBF process and predicting surface roughness using a convolutional neural network. Experimental results show the network's ability to accurately predict surface roughness, laying the foundation for future research on linking hyperspectral process images to relevant part properties for quality assurance purposes.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Christian Nowroth, Tiansheng Gu, Jan Grajczak, Sarah Nothdurft, Jens Twiefel, Joerg Hermsdorf, Stefan Kaierle, Joerg Wallaschek
Summary: Laser beam welding is widely used in industry and research. This study proposes using deep learning for semantic segmentation of micrographs of complex weld areas to achieve automatic detection and quantization of weld seam properties. The trained model achieves good results in weld contour detection and mean intersection over union.
APPLIED SCIENCES-BASEL
(2022)
Article
Materials Science, Multidisciplinary
Kai Biester, Alexander Barroi, Tjorben Bokelmann, Marius Lammers, Joerg Hermsdorf, Stefan Kaierle
Summary: In this study, laser-assisted double-wire welding with a nontransferred arc and beam shaping optics was used for cladding workpieces. The results show that the contact angles of the weld beads produced with the line optics are slightly different from those obtained by oscillating the laser beam, and the required laser power is 1.5-2 times greater.
JOURNAL OF LASER APPLICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Sarah Nothdurft, Oliver Seffer, Joerg Hermsdorf, Ludger Overmeyer, Stefan Kaierle
Summary: There is a strong ambition to switch from combustion technology to battery-electric drives, and laser beam welding is found to be a suitable technology in battery production. This research studies welding approaches with different laser beam sources in order to develop high-quality welds with high electrical conductivity.
JOURNAL OF LASER APPLICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Oliver Seffer, Sarah Nothdurft, Alexander Hilck, Michael Hustedt, Joerg Hermsdorf, Stefan Kaierle
Summary: This article introduces the commonly used arc welding and laser-arc hybrid welding techniques for joining thick steel plates, comparing their advantages and disadvantages. Additionally, experiments are conducted using high-power diode laser beam welding to investigate the impact of plate thickness on weld seam quality and characteristics. The results demonstrate that high-quality single-layer welding of relatively thick plates can be achieved with suitable process parameters.
JOURNAL OF LASER APPLICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Nick Schwarz, Marius Lammers, Joerg Hermsdorf, Stefan Kaierle, Henning Ahlers, Roland Lachmayer
Summary: Coaxial laser wire directed energy deposition enables the buildup of near net shape geometries and surface coatings in any direction. By introducing two different wire materials, it allows for in situ alloying or functionally graded structures. This study investigates the intermixing behavior of wires with varying element contents using a multiple diode coaxial laser processing head.
JOURNAL OF LASER APPLICATIONS
(2023)
Article
Optics
Kay Bischoff, Stefan Kefer, Alexander Wienke, Ludger Overmeyer, Stefan Kaierle, Cemal Esen, Ralf Hellmann
Summary: This study demonstrates and discusses the integration of Bragg gratings in aerosol-jetted polymer optical waveguides through the OPTAVER process. By using a femtosecond laser and adaptive beam shaping, periodic single pulse modifications are generated in the waveguide material to form Bragg gratings. Integration of a single grating structure or an array of Bragg grating structures in the multimode waveguide produces a pronounced reflection signal with non-Gaussian shapes. The main wavelength of reflection can be evaluated through an appropriate smoothing algorithm and a significant Bragg wavelength shift is detected when loaded by mechanical bending.
Article
Materials Science, Multidisciplinary
Michael Desens, Katharina Rettschlag, Peter Jaeschke, Stefan Kaierle
Summary: Welding of quartz glass is currently done manually using gas torches, but this method is inefficient and can result in uneven welds. An automated laser welding process is proposed as a more energy-efficient and repeatable solution, which also addresses the shortage of skilled labor. The study focuses on welding quartz glass plates at an angle using fiber or rod as filler material, aiming to achieve homogeneous welds with minimal defects.
JOURNAL OF LASER APPLICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Rabi Lahdo, Sarah Nothdurft, Oliver Seffer, Joerg Hermsdorf, Stefan Kaierle
Summary: Thick dissimilar joints of steel and aluminum are of high interest in shipbuilding to reduce weight and improve ship stability. The current explosive-welded adapter is complex, time-consuming, and expensive, therefore, a better alternative is needed. In this study, laser beam welding processes were developed to join steel and aluminum using iron welding powder as a filler material, resulting in improved weld quality and mechanical properties.
JOURNAL OF LASER APPLICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Daniel Maiwald, Sarah Nothdurft, Joerg Hermsdorf, Stefan Kaierle
Summary: Brass is an important component in the copper alloy group, and laser beam welding of this alloy has great potential. However, there are challenges such as irregular seam surfaces and formation of pores and spatters. Recent developments in high-brilliance near-infrared laser beam sources with adjustable beam profiles have contributed to stabilizing the welding process. Process parameters, such as energy per unit length, spot size, and process gas supply, have a significant impact on the resulting weld seam quality.
JOURNAL OF LASER APPLICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Laura Budde, Nick Schwarz, Joerg Hermsdorf, Stefan Kaierle, Ludger Overmeyer
Summary: This study investigates the application of the ABA cladding strategy in coaxial wire-based cladding processes. The results suggest that adjusting welding parameters can significantly reduce waviness but may result in an increase in lack of fusion defects.
JOURNAL OF LASER APPLICATIONS
(2023)
Article
Engineering, Manufacturing
Tabea Marie Demke, Nicole Emminghaus, Ludger Overmeyer, Stefan Kaierle, Christian Klose, Susanne Elisabeth Thuerer, Berend Denkena, Benjamin Bergmann, Florian Schaper, Peter Nyhuis, Vivian Katharina Kuprat
Summary: This paper presents an approach for a semi-quantitative procedure for the monetary evaluation of process innovations in the early innovation phase, focusing on manufacturing and material costs. The approach links value drivers of Economic Value Added (EVA) and innovation-driven factors influencing EVA, using a driver tree and an impact model. Data is collected through expert interviews and a weighted scoring model is used to draw a semi-quantitative conclusion regarding the EVA achieved by the process innovation. The practical application of the approach shows that the current implementation of process innovations in oxygen-free production does not effectively achieve EVA, but corresponding levers can be identified to positively influence EVA and the industrialization of the process innovation. Further steps are identified to evolve the presented approach into a complete method for monetary innovation evaluation in early innovation phases.
PRODUCTION ENGINEERING-RESEARCH AND DEVELOPMENT
(2023)
Article
Engineering, Industrial
L. Budde, K. Biester, M. Lammers, J. Hermsdorf, S. Kaierle, L. Overmeyer
Summary: The study investigates the influence of process parameters on weld seam geometry and process stability when welding AISI 52100 bearing steel using the laser hot-wire cladding process. The stability of the process is evaluated by determining a process window based on actual and set values for the wire feed rate and current parameters. The weld seams are measured and analyzed in terms of width, height, contact angle, and shape. The effect of the process parameters on the weld seam geometry is studied, and mathematical functions such as parabolic, cosinusoidal, and circular arc are used to describe the geometry. However, no clearly significant result is found, with only a trend towards the circular arc and parabolic functions.
ADVANCES IN INDUSTRIAL AND MANUFACTURING ENGINEERING
(2023)
Article
Engineering, Industrial
Nicole Emminghaus, Sebastian Fritsch, Hannes Buttner, Jannes August, Marijan Tegtmeier, Michael Huse, Marius Lammers, Christian Hoff, Jorg Hermsdorf, Stefan Kaierle
Summary: This paper presents a new method to achieve an oxygen-free processing atmosphere by doping argon shielding gas with reactive monosilane to reduce residual oxygen content to a range comparable to Extreme High Vacuum. It was found that metallic materials and smooth surfaces are favorable for design in silane-containing atmosphere, while polymers are likely to degrade.
ADVANCES IN INDUSTRIAL AND MANUFACTURING ENGINEERING
(2021)
Article
Engineering, Manufacturing
H. Ohrdes, S. Nothdurft, C. Nowroth, J. Grajczak, J. Twiefel, J. Hermsdorf, S. Kaierle, J. Wallaschek
Summary: The study explores the introduction of ultrasonic vibrations into laser beam welding, determining the best system design for optimal weld shape. Through experiments and simulations, the effects of ultrasonic vibrations on the weld shape are analyzed and it is found that amplitudes over 4 μm can disturb the weld shape.
PRODUCTION ENGINEERING-RESEARCH AND DEVELOPMENT
(2021)
