Welding Process for the Additive Manufacturing of Cantilevered Components with the WAAM

Wire arc additive manufacturing (WAAM) is a direct energy deposition (DED) process with high deposition rates, but deformation and distortion can occur due to the high energy input and resulting strains. Despite great efforts, the prediction of distortion and resulting geometry in additive manufacturing processes using WAAM remains challenging. In this work, an artificial neural network (ANN) is established to predict welding distortion and geometric accuracy for multilayer WAAM structures. For demonstration purposes, the ANN creation process is presented on a smaller scale for multilayer beads on plate welds on a thin substrate sheet. Multiple concepts for the creation of ANNs and the handling of outliers are developed, implemented, and compared. Good results have been achieved by applying an enhanced ANN using deformation and geometry from the previously deposited layer. With further adaptions to this method, a prediction of additive welded structures, geometries, and shapes in defined segments is conceivable, which would enable a multitude of applications for ANNs in the WAAM-Process, especially for applications closer to industrial use cases. It would be feasible to use them as preparatory measures for multi-segmented structures as well as an application during the welding process to continuously adapt parameters for a higher resulting component quality.

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Visual-Based Multi-Section Welding Path Generation Algorithm

Processes ◽

10.3390/pr8070821 ◽

2020 ◽

Vol 8 (7) ◽

pp. 821

Author(s):

Hong Lu ◽

Mingtian Ma ◽

Shu Liu ◽

Essa Alghannam ◽

Yue Zang ◽

...

Keyword(s):

Additive Manufacturing ◽

Welding Process ◽

Automatic Welding ◽

Path Generation ◽

Test Plate ◽

Welded Steel ◽

Generation Algorithm ◽

Experiment Platform ◽

Welding Equipment ◽

Important Form

As an important form of additive manufacturing, welding is widely used in steel components welding work of construction, shipbuilding and other fields. In this study, an intelligent welding path generation algorithm based on multi-section interpolation is proposed in order to deal with non-standard multi-pass welding grooves which are difficult to be handled by automatic welding equipment in the construction site. Firstly, the non-standard grooves are classified and the reasons for their occurrence are discussed. Secondly, an automatic welding additive manufacturing system framework is discussed and an appropriate detection method is selected. Then, combining with the welding standard of non-standard grooves and the characteristics of the welding process, a multi-section interpolation-based welding path generation algorithm is proposed. Finally, a visual experiment platform was built to detection the typical non-standard groove and the welding experiment is implemented to verify the feasibility of the algorithm. According to the path generated by the algorithm, the welded steel components test plate meets the actual engineering standard after quality inspection. The experimental results and simulation results conclude the algorithm can be used to generate the welding path of the non-standard groove.

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Process planning based on cylindrical or conical surfaces for five-axis wire and arc additive manufacturing

Rapid Prototyping Journal ◽

10.1108/rpj-01-2020-0001 ◽

2020 ◽

Vol 26 (8) ◽

pp. 1405-1420

Author(s):

Fusheng Dai ◽

Haiou Zhang ◽

Runsheng Li

Keyword(s):

Additive Manufacturing ◽

Path Planning ◽

Process Planning ◽

Flat Surface ◽

Welding Process ◽

Planning Method ◽

Content Type ◽

Tool Paths ◽

Conical Surfaces ◽

Five Axis

Purpose The study aims to fabricate large metal components with overhangs built on cylindrical or conical surfaces with a high dimensional precision. It proposes methods to address the problems of generating tool-paths on cylindrical or conical surfaces simply and precisely, and planning the welding process on these developable surfaces. Design/methodology/approach The paper presents the algorithm of tool-paths planning on conical surfaces using a parametric slicing equation and a spatial mapping method and deduces the algorithm of five-axis transformation by addressing the rotating question of two sequential points. The welding process is investigated with a regression fitting model on a flat surface, and experimented on a conical surface, which can be flattened onto a flat surface. Findings The paper provides slicing and path-mapping expressions for cylindrical and conical surfaces and a curvature-speed-width (CSW) model for wire and arc additive manufacturing to improve the surface appearances. The path-planning method and CSW model can be applied in the five-axis fabrication of the prototype of an underwater thruster. The CSW model has a confidence coefficient of 98.02% and root mean squared error of 0.2777 mm. The reverse measuring of the finished blades shows the residual deformation: an average positive deformation of about 0.5546 mm on one side of the blades and an average negative deformation of about −0.4718 mm on the other side. Research limitations/implications Because of the chosen research approach, the research results may lack generalizability for the fabrication based on arbitrary surfaces. Originality/value This paper presented an integrated slicing, tool-path planning and welding process planning method for five-axis wire and arc additive manufacturing.

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Investigating Predictive Metamodeling for Additive Manufacturing

Volume 1A: 36th Computers and Information in Engineering Conference ◽

10.1115/detc2016-60506 ◽

2016 ◽

Cited By ~ 3

Author(s):

Zhuo Yang ◽

Douglas Eddy ◽

Sundar Krishnamurty ◽

Ian Grosse ◽

Peter Denno ◽

...

Keyword(s):

Additive Manufacturing ◽

Welding Process ◽

Disruptive Technology ◽

Mathematical Framework ◽

Future Directions ◽

Process Plans ◽

Complex Relationships ◽

Physical Phenomena ◽

Potential Use

Additive manufacturing (AM) is a new and disruptive technology that comes with a set of unique challenges. One of them is the lack of understanding of the complex relationships between the numerous physical phenomena occurring in these processes. Metamodels can be used to provide a simplified mathematical framework for capturing the behavior of such complex systems. At the same time, they offer a reusable and composable paradigm to study, analyze, diagnose, forecast, and design AM parts and process plans. Training a metamodel requires a large number of experiments and even more so in AM due to the various process parameters involved. To address this challenge, this work analyzes and prescribes metamodeling techniques to select optimal sample points, construct and update metamodels, and test them for specific and isolated physical phenomena. A simplified case study of two different laser welding process experiments is presented to illustrate the potential use of these concepts. We conclude with a discussion on potential future directions, such as data and model integration while also accounting for sources of uncertainty.

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Development of a Resistance Spot Welding Process Using Additive Manufacturing

Metals ◽

10.3390/met10050555 ◽

2020 ◽

Vol 10 (5) ◽

pp. 555 ◽

Cited By ~ 1

Author(s):

Márcio Batista ◽

Valdir Furlanetto ◽

Sérgio Duarte Brandi

Keyword(s):

Additive Manufacturing ◽

Tensile Stress ◽

Resistance Spot Welding ◽

Spot Welding ◽

Manufacturing Industry ◽

Low Cost ◽

Welding Process ◽

Chemical Compositions ◽

Automotive Manufacturing ◽

Resistance Spot

For several decades, the electrical resistance spot welding process has been widely used in the manufacturing of sheet metal structures, especially in automotive bodies. During this period there was no significant development for this welding process. However, in recent years, in order to meet the demand for lighter, economical, and low-cost vehicles, the automotive manufacturing industry is undergoing a revolution in the use of high strength steel sheet combinations, chemical compositions, and of different thicknesses. In this context, the present work focuses on the study and development of a new resistant spot welding technology using additive manufacturing (AMSW) in zinc-coated steel sheets, used in the automotive industry. As a comparison, spot welding was also performed by the conventional resistance spot welding process (RSW). The results showed that the spot welding process using additive manufacturing (AMSW), through the optimized parameters, compared to the conventional resistance spot welding process (RSW), was 34.47% higher in relation to the shear tensile stress, as well as 28.57% higher tensile stress with a perpendicular load to the weld spot. The indentation or thermomechanical mark on the surface of the sheet was imperceptible to the visual inspection, producing a smooth face in the spot region.

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Effect of Phase Transformations on Scanning Strategy in WAAM Fabrication

Materials ◽

10.3390/ma14247871 ◽

2021 ◽

Vol 14 (24) ◽

pp. 7871

Author(s):

Muhammad Hassaan Ali ◽

You Sung Han

Keyword(s):

Residual Stress ◽

Additive Manufacturing ◽

Residual Stresses ◽

Phase Transformations ◽

Manufacturing Industry ◽

Welding Process ◽

Stress Generation ◽

Temperature History ◽

History Of ◽

Wire Arc Additive Manufacturing

Due to its high production rates and low cost as compared to other metal additive manufacturing processes, wire arc additive manufacturing (WAAM) has become an emerging technology in the manufacturing industry. However, the residual stress generation and part distortion hinder its widespread adoption because of the complex thermal build-histories of WAAM parts. One of the ways to alleviate this problem is to consider the effects of scan strategies as it directly influences the thermal history of the built part. Since WAAM itself is an evolved welding process and even though it is evident from welding studies that phase transformations directly affect the residual stresses in welded parts, it remains unclear how the consideration of phase transformations for different scan strategies will affect the residual stresses and distortions in the WAAMed parts. A FEM study has been performed to elucidate the effects of phase transformations on residual stresses and the distortion for different deposition patterns. The current findings highlight that for the fabrication of low-carbon martensitic steels: The consideration of phase transformations for line-type discontinuous patterns (alternate and raster) do not significantly affect the residual stresses. Consideration of phase transformations significantly affects residual stresses for continuous patterns (zigzag, in–out and out–in). To accurately simulate complex patterns, phase transformations should be considered because the patterns directly influence the temperature history of the built part and will thus affect the phase transformations, the residual stresses and the warpage. During the fabrication of WAAM parts, whenever possible, discontinuous line scanning patterns should be considered as they provide the part with uniform residual stress and distortion. The alternate line pattern has been found to be the most consistent overall pattern.

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Properties and anisotropy behaviour of a nickel base alloy material produced by robot-based wire and arc additive manufacturing

Welding in the World ◽

10.1007/s40194-020-00971-7 ◽

2020 ◽

Vol 64 (11) ◽

pp. 1921-1931

Author(s):

Thomas Hassel ◽

Torben Carstensen

Keyword(s):

Additive Manufacturing ◽

Anisotropic Material ◽

High Performance ◽

Base Alloy ◽

Deformation Behaviour ◽

Welding Process ◽

Polished Surface ◽

Metal Powders ◽

Material Behaviour ◽

Process Technology

Abstract In order to produce three-dimensional components from metals, a wide variety of processes exist. Laser processes combined with metal powders are frequently used and developed. Restrictive factors are the machine-related small workspace, the machinery costs and the material portfolio, which place the technology in the area of high-performance components. Wire and arc additive manufacturing (WAAM), as a robust and economical welding process technology in combination with robot applications, represents an option to become more size-independent and provides variability in the range of materials. This work shows results for the robot-based WAAM of structures made from nickel alloy 617. The main focus of the investigation was the determination of the mechanical properties in the as-welded state for which static strength tests, microhardness and metallographic studies were carried out. The anisotropic material behaviour in relation to the build direction (BD) was tested. The direction-dependent strength properties of single-track welded structures are presented with samples taken and tested at 0°, 45° and 90° to the BD. The deformation behaviour was investigated by micro-tensile tests in a scanning electron microscope, whereby the formation of sliding steps on the polished surface under tensile stress was studied. The anisotropic behaviour of the WAAM structures is discussed under consideration of the microstructure and with regard to the grain size development and phase formation. The results indicate an anisotropic material behaviour in the as-welded state based of the crystallographic orientation of the material.

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Analysis of the Behavior of Dynamic Resistance, Electrical Energy and Force between the Electrodes in Resistance Spot Welding Using Additive Manufacturing

Metals ◽

10.3390/met10050690 ◽

2020 ◽

Vol 10 (5) ◽

pp. 690

Author(s):

Márcio Batista ◽

Valdir Furlanetto ◽

Sérgio Duarte Brandi

Keyword(s):

Thermal Expansion ◽

Additive Manufacturing ◽

Resistance Spot Welding ◽

Spot Welding ◽

Welding Process ◽

Electrical Energy ◽

Dynamic Resistance ◽

Low Carbon ◽

Resistance Spot ◽

Welding Spot

This work is aimed at the analysis of the dynamic resistance, electrical energy and behavior of the force between electrodes (including thermal expansion) during welding at optimized parameters, referring to the process of spot welding using additive manufacturing (AMSW). For comparative purposes, this analysis also includes the conventional resistance spot welding process (RSW). The experiments were done on low carbon-zinc-coated sheets used in the automotive industry. The results regarding the welding process using additive manufacturing (AMSW), in comparison to the conventional resistance spot welding (RSW), showed that the dynamic resistance presented a different behavior due to the collapse of the deposition at the beginning of the welding, and that a smaller magnitude of electrical energy (approximately <3.35 times) is required to produce a welding spot approved in accordance with the norm. No force of thermal expansion was observed during the passage of the current, in contrast, there was a decrease in the force between the electrodes due to the collapse of the deposition at the beginning of the welding.

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In Situ Production of Titanium Aluminides during Wire Arc Additive Manufacturing with Hot-Wire Assisted GMAW Process

Metals ◽

10.3390/met9050578 ◽

2019 ◽

Vol 9 (5) ◽

pp. 578 ◽

Cited By ~ 2

Author(s):

Philipp Henckell ◽

Yarop Ali ◽

Andreas Metz ◽

Jean Pierre Bergmann ◽

Jan Reimann

Keyword(s):

Additive Manufacturing ◽

Titanium Aluminides ◽

Gas Metal Arc Welding ◽

Welding Process ◽

Alloy Formation ◽

Layer By Layer ◽

Feeding Rates ◽

Hot Wire ◽

Wire Arc Additive Manufacturing

As part of a feasibility study, an alternative production process for titanium aluminides was investigated. This process is based on in situ alloying by means of a multi-wire technique in the layer-wise additive manufacturing process. Thereby, gas metal arc welding (GMAW) was combined with additional hot-wire feeding. By using two separate wires made of titanium and aluminum, it is possible to implement the alloy formation of titanium aluminides directly in the weld bead of the welding process. In this study, wall structures were built layer-by-layer with alloy compositions between 10 at% and 55 at% aluminum by changing the feeding rates. During this investigation, the macroscopic characteristics, microstructural formation, and the change of the microhardness values were analyzed. A close examination of the influence of welding speed and post-process heat treatment on the Ti–47Al alloy was performed; this being particularly relevant due to its economically wide spread applications.

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WAAM Application for EPC Company

MATEC Web of Conferences ◽

10.1051/matecconf/201926905002 ◽

2019 ◽

Vol 269 ◽

pp. 05002

Author(s):

Priyantomo Agustinus Ananda

Keyword(s):

Additive Manufacturing ◽

Manufacturing Process ◽

Complex Geometry ◽

Welding Process ◽

Feed Speed ◽

Layer By Layer ◽

Delivery Time ◽

Project Schedule ◽

Wide Range ◽

Wire Arc Additive Manufacturing

WAAM ( Wire + Arc Additive Manufacturing) is a process of adding material layer by layer in order to build a near net shape components. It shows a further promising future for fabricating large expensive metal components with complex geometry. Engineering Procurement and Construction (EPC) company as one of the industrial section which related with engineering design and products, wide range of material type, and shop based or site based manufacturing process have been dealing with conventional manufacturing and procurement process in order to fulfill its requirement for custom parts and items for the project completion purpose. During the conventional process, there is a risk during the transportation of the products from the manufacturing shop to then site project, this risk is even greater when the delivery time take part as one of the essential part which affect the project schedule. Wire Arc Additive Manufacturing process offering an alternative process to shorten the delivery time and process for a selected material and engineered items, with the consideration of essential variables which can affect the final products of WAAM process, such as : heat input, wire feed speed, travel speed, shielding gas, welding process and robotic system applied. In this paper, the possibilities of WAAM application in EPC company will be assessed, an in depth literature review of the various process which possible to applied, include the loss and benefit compared with conventional method will be presented. The main objective is to identify the current challenge and the prospect of WAAM application in EPC company.

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