A Literature Review on the Wire and Arc Additive Manufacturing—Welding Systems and Software

2021 ◽  
Vol 13 (8) ◽  
pp. 1391-1400
Author(s):  
Zidong Lin ◽  
Pengfei Liu ◽  
Xinghua Yu
Keyword(s):  
Additive Manufacturing ◽  
Large Scale ◽  
Tool Path ◽  
Future Research ◽  
High Deposition Rate ◽  
Efficient Technology ◽  
The Past ◽  
Material Efficiency ◽  
Systems Software ◽  
Design Generation

Wire and arc additive manufacturing (WAAM) is considered to be an economic and efficient technology that is suitable to produce large-scale and ultra-large-scale metallic components. In the past two decades, it has been widely investigated in different fields, such as aerospace, automotive and marine industries. Due to its relatively high deposition rate, material efficiency, and shortened lead time compared to other powder-based additive manufacturing (AM) techniques, wire and arc additive manufacturing (WAAM) has been significantly noticed and adopted by both academic researchers and industrial engineers. In order to summarize the development achievements of wire and arc additive manufacturing (WAAM) in the past few years and outlook the development direction in the coming days, this paper provides an overview of 3D metallic printing by applying it as a deposition method. The review mainly focuses on the current welding systems, software for tool path design, generation, and planning used in wire and arc additive manufacturing (WAAM). In the end, the state of the art and future research on wire and arc additive manufacturing (WAAM) have been prospected.

Control of humping phenomenon and analyzing mechanical properties of Al–Si wire-arc additive manufacturing fabricated samples using cold metal transfer process

2021 ◽  
pp. 095440622199840
Author(s):  
Yashwant Koli ◽  
N Yuvaraj ◽  
Aravindan Sivanandam ◽  
Vipin
Keyword(s):  
Mechanical Properties ◽  
Additive Manufacturing ◽  
Heat Input ◽  
Large Scale ◽  
High Deposition Rate ◽  
Bead Geometry ◽  
Layer By Layer ◽  
Cold Metal Transfer ◽  
Geometrical Shapes ◽  
Wire Arc Additive Manufacturing

Nowadays, rapid prototyping is an emerging trend that is followed by industries and auto sector on a large scale which produces intricate geometrical shapes for industrial applications. The wire arc additive manufacturing (WAAM) technique produces large scale industrial products which having intricate geometrical shapes, which is fabricated by layer by layer metal deposition. In this paper, the CMT technique is used to fabricate single-walled WAAM samples. CMT has a high deposition rate, lower thermal heat input and high cladding efficiency characteristics. Humping is a common defect encountered in the WAAM method which not only deteriorates the bead geometry/weld aesthetics but also limits the positional capability in the process. Humping defect also plays a vital role in the reduction of hardness and tensile strength of the fabricated WAAM sample. The humping defect can be controlled by using low heat input parameters which ultimately improves the mechanical properties of WAAM samples. Two types of path planning directions namely uni-directional and bi-directional are adopted in this paper. Results show that the optimum WAAM sample can be achieved by adopting a bi-directional strategy and operating with lower heat input process parameters. This avoids both material wastage and humping defect of the fabricated samples.

scholarly journals TheChildLab.com A Video Chat Platform for Developmental Research

2018 ◽  
Author(s):  
Mark Sheskin ◽  
Frank Keil
Keyword(s):  
Large Scale ◽  
Longitudinal Research ◽  
Cross Cultural ◽  
Mechanical Turk ◽  
Future Research ◽  
Psychology Research ◽  
Developmental Research ◽  
The Past ◽  
Adult Participants ◽  
Amazon's Mechanical Turk

Over the past decade, the internet has become an important platform for many types of psychology research, especially research with adult participants on Amazon’s Mechanical Turk. More recently, developmental researchers have begun to explore how online studies might be conducted with infants and children. Here, we introduce a new platform for online developmental research that includes live interaction with a researcher, and use it to replicate classic results in the literature. We end by discussing future research, including the potential for large-scale cross-cultural and longitudinal research.

Feasibility and Characterization of Large-Scale Additive Manufacturing With Long Fiber Reinforced Composites

2020 ◽  
Author(s):  
Aditya R. Thakur ◽  
Ming C. Leu ◽  
Xiangyang Dong
Keyword(s):  
Additive Manufacturing ◽  
Carbon Fiber ◽  
Carbon Fibers ◽  
Large Scale ◽  
Flexural Modulus ◽  
High Deposition Rate ◽  
Reinforced Composites ◽  
Fiber Reinforced ◽  
Continuous Fiber ◽  
Long Carbon Fibers

Abstract A new additive manufacturing (AM) approach to fabricate long fiber reinforced composites (LFRC) was proposed in this study. A high deposition rate was achieved by the implementation of a single-screw extruder, which directly used thermoplastic pellets and continuous fiber tows as feedstock materials. Thus, the proposed method was also used as a large-scale additive manufacturing (LSAM) method for printing large-volume components. Using polylactic acid (PLA) pellets and continuous carbon fiber tows, the feasibility of the proposed AM method was investigated through printing LFRC samples and further demonstrated by fabricating large-volume components with complex geometries. The printed LFRC samples were compared with pure thermoplastic and continuous fiber reinforced composite (CFRC) counterparts via mechanical tests and microstructural analyses. With comparable flexural modulus, the flexural strength of the LFRC samples was slightly lower than that of the CFRC samples. An average improvement of 28% in flexural strength and 50% in flexural modulus were achieved compared to those of pure PLA parts, respectively. Discontinuous long carbon fibers, with an average fiber length of 20.1 mm, were successfully incorporated into the printed LFRC samples. The carbon fiber orientation, distribution of carbon fiber length, and dispersion of carbon fiber as well as porosity were further studied. The carbon fibers were highly oriented along the printing direction with a relatively uniformly distributed fiber reinforcement across the LFRC cross section. With high deposition rate (up to 0.8 kg/hr) and low material costs (< $10/kg), this study demonstrated the potentials of the proposed printing method in LSAM of high strength polymer composites reinforced with long carbon fibers.

Improvement in Geometrical Accuracy and Mechanical Property for Arc-Based Additive Manufacturing Using Metamorphic Rolling Mechanism

2016 ◽  
Vol 138 (11) ◽  
Author(s):  
Yang Xie ◽  
Haiou Zhang ◽  
Fei Zhou
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Additive Manufacturing ◽  
Large Scale ◽  
Vertical Direction ◽  
Shrinkage Porosity ◽  
Hybrid Manufacturing ◽  
High Deposition Rate ◽  
Geometrical Accuracy ◽  
Rolling Mechanism

Additive manufacturing (AM), or 3D printing, is drawing considerable contemporary interest due to its characteristics of high material utilization, great flexibility in product design, and inherent moldless process. Arc-based AM (AAM) is a promising AM method with high deposition rate and favorable buildup quality. Components made by AAM are fabricated through superimposed weld beads deposited from metal wire. Unlike laser-based additive manufacturing, AAM is more difficult to control. Because of the large energy input of the energy source and the liquidity of the melting metal material, bottleneck problems like shrinkage porosity, cracking, residual stresses, and deformation occur. Resultant poor geometrical accuracy and mechanical property keep AAM from industrial application. Especially in the aerospace industry, structural and mechanical property specifications are stringent and critical. This paper presents a novel hybrid manufacturing method by using hot-rolling process to assist the arc welding to solve the above problems. Initially, a miniature metamorphic rolling mechanism (MRM) was developed using metamorphic mechanism theory. Configuration and topology of the MRM can change according to the feature of the components to roll the top and lateral surfaces of the bead. Subsequently, three single-pass multilayer walls were built, respectively, for comparison. The rolled results show significant improvement in geometrical accuracy of the built features. Tensile test results demonstrate improvement in mechanical properties. The improved mechanical properties of rolled specimens are superior to wrought material in travel direction. Microstructure comparisons indicate columnar grains observed in vertical direction and fusion zones were suppressed. Eventually, fabrication of a large-scale aerospace component validates the feasibility of industry application for the hybrid manufacturing technology.

scholarly journals Finite Element Modeling and Validation of Metal Deposition in Wire Arc Additive Manufacturing

2021 ◽  
pp. 61-66
Author(s):  
Akram Chergui ◽  
Nicolas Beraud ◽  
Frédéric Vignat ◽  
François Villeneuve
Keyword(s):  
Finite Element ◽  
Additive Manufacturing ◽  
Large Scale ◽  
Low Cost ◽  
Source Model ◽  
Metal Deposition ◽  
High Deposition Rate ◽  
Element Technique ◽  
Metallic Parts ◽  
Wire Arc Additive Manufacturing

AbstractWire arc additive manufacturing allows the production of metallic parts by depositing beads of weld metal using arc-welding technologies. This low-cost additive manufacturing technology has the ability to manufacture large-scale parts at a high deposition rate. However, the quality of the obtained parts is greatly affected by the various thermal phenomena present during the manufacturing process. Numerical simulation remains an effective tool for studying such phenomena. In this work, a new finite element technique is proposed in order to model metal deposition in WAAM process. This technique allows to gradually construct the mesh representing the deposited regions along the deposition path. The heat source model proposed by Goldak is adapted and combined with the proposed metal deposition technique taking into account the energy distribution between filler material and the molten pool. The effectiveness of the proposed method is validated by series of experiments, of which an example is detailed in this paper.

scholarly journals Vision-Based Melt Pool Monitoring for Wire-Arc Additive Manufacturing Using Deep Learning Method

2021 ◽  
Author(s):  
Chunyang Xia ◽  
Zengxi Pan ◽  
Yuxing Li ◽  
Huijun Li
Keyword(s):  
Deep Learning ◽  
Additive Manufacturing ◽  
Large Scale ◽  
Deposition Process ◽  
Utilization Rate ◽  
High Deposition Rate ◽  
Promising Alternative ◽  
Visual Monitoring ◽  
Melt Pool ◽  
Wire Arc Additive Manufacturing

Abstract Wire-arc additive manufacturing (WAAM) technology has been widely recognized as a promising alternative for fabricating large-scale components, due to its advantages of high deposition rate and high material utilization rate. However, some anomalies may occur during the deposition process, such as humping, spattering, and robot suspend. this study proposed to apply Deep Learning in the visual monitoring to diagnose different anomalies during WAAM process. The melt pool images of different anomalies were collected for training and validation by a visual monitoring system. The classification performance of several representative CNN architectures, including ResNet, EfficientNet, VGG-16 and GoogLeNet, were investigated and compared. The classification accuracy of 97.62%, 97.45%, 97.15% and 97.25% was achieved by each model. The results proved that the CNN models are effective in classifying different types of melt pool images of WAAM. Our study is applicable beyond WAAM and should benefit other additive manufacturing or arc welding techniques.

scholarly journals A design for additive manufacturing case study: fingerprint stool on a BigRep ONE

2019 ◽  
Vol 25 (6) ◽  
pp. 1069-1079 ◽  
Author(s):  
James I. Novak ◽  
Jonathon O’Neill
Keyword(s):  
Additive Manufacturing ◽  
Large Scale ◽  
Future Research ◽  
Design For Additive Manufacturing ◽  
Fused Filament Fabrication ◽  
Content Type ◽  
Layer Height ◽  
Design Engineers ◽  
Final Design

Purpose This paper aims to present new qualitative and quantitative data about the recently released “BigRep ONE” 3 D printer led by the design of a one-off customized stool. Design/methodology/approach A design for additive manufacturing (DfAM) framework was adopted, with simulation data iteratively informing the final design. Findings Process parameters can vary manufacturing costs of a stool by over AU$1,000 and vary print time by over 100 h. Following simulation, designers can use the knowledge to inform iteration, with a second variation of the design being approximately 50 per cent cheaper and approximately 50 per cent faster to manufacture. Metrology data reveal a tolerance = 0.342 per cent in overall dimensions, and surface roughness data are presented for a 0.5 mm layer height. Research limitations/implications Led by design, this study did not seek to explore the full gamut of settings available in slicing software, focusing predominantly on nozzle diameter, layer height and number of walls alongside the recommended settings from BigRep. The study reveals numerous areas for future research, including more technical studies. Practical implications When knowledge and techniques from desktop 3 D printing are scaled up to dimensions measuring in meters, new opportunities and challenges are presented for design engineers. Print times and material costs in particular are scaled up significantly, and this study provides numerous considerations for research centers, 3 D printing bureaus and manufacturers considering large-scale fused filament fabrication manufacturing. Originality/value This is the first peer-reviewed study involving the BigRep ONE, and new knowledge is presented about the practical application of the printer through a design-led project. Important relationships between material volume/cost and print time are valuable for early adopters.

scholarly journals Application of Fe(VI) in abating contaminants in water: State of art and knowledge gaps

2020 ◽  
Vol 15 (5) ◽  
Author(s):  
Shuchang Wang ◽  
Binbin Shao ◽  
Junlian Qiao ◽  
Xiaohong Guan
Keyword(s):  
Organic Contaminants ◽  
Large Scale ◽  
Rapid Development ◽  
Future Research ◽  
The Past ◽  
Water State ◽  
Potential Formation ◽  
Oxidation Technology ◽  
Important Nodes

Abstract The past two decades have witnessed the rapid development and wide application of Fe(VI) in the field of water de-contamination because of its environmentally benign character. Fe(VI) has been mainly applied as a highly efficient oxidant/disinfectant for the selective elimination of contaminants. The in situ generated iron(III) (hydr)oxides with the function of adsorption/coagulation can further increase the removal of contaminants by Fe(VI) in some cases. Because of the limitations of Fe(VI) per se, various modified methods have been developed to improve the performance of Fe(VI) oxidation technology. Based on the published literature, this paper summarized the current views on the intrinsic properties of Fe(VI) with the emphasis on the self-decay mechanism of Fe(VI). The applications of Fe (VI) as a sole oxidant for decomposing organic contaminants rich in electron-donating moieties, as a bi-functional reagent (both oxidant and coagulant) for eliminating some special contaminants, and as a disinfectant for inactivating microorganisms were systematically summarized. Moreover, the difficulties in synthesizing and preserving Fe(VI), which limits the large-scale application of Fe (VI), and the potential formation of toxic byproducts during Fe(VI) application were presented. This paper also systematically reviewed the important nodes in developing methods to improve the performance of Fe(VI) as oxidant or disinfectant in the past two decades, and proposed the future research needs for the development of Fe(VI) technologies.

scholarly journals Characterization of emerging predominant HFMD pathogen, coxsackievirus A6 in mainland China

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
Y Song ◽  
Y Zhang ◽  
W B Xu
Keyword(s):  
Public Health ◽  
Health Problem ◽  
Large Scale ◽  
Mainland China ◽  
Public Health Problem ◽  
Clinical Samples ◽  
Future Research ◽  
Surveillance Network ◽  
The Past ◽  
Coxsackievirus A6

Abstract Hand, foot, and mouth disease (HFMD) had the highest yearly incidence, with over 10 million cases of HFMD annually reported in China. Enterovirus A71 (EV-A71) and coxsackievirus A16 (CV-A16) have been regarded as the leading pathogens of HFMD outbreaks worldwide and in China; however, in recent years, the leading pathogens have been changing, as large outbreaks of CV-A6-associated HFMD have been reported worldwide. Since 2013, repeated large-scale HFMD outbreaks caused by CV-A6 happened in mainland China, where, as a result, CV-A6 has surpassed EV-A71 and CV-A16 as the leading HFMD pathogen in most Chinese provinces. We sequenced the whole genomes of 158 CV-A6 clinical samples that were isolated between 2010 and 2018 from the HFMD Surveillance Network established in our laboratory. Our results showed that: seven recombination forms (RFs) of Chinese CV-A6 were detected; different CV-A6 RFs showed distinct virulence and transmissibility; VP1283T may play an important role in the virulence of Chinese CV-A6. HFMD epidemics in China have become a serious public health problem over the past decade. In this research, we have attempted to explore the causes of the high transmissibility of the emerging CV-A6 in mainland China on the basis of CV-A6 evolution based on 336 whole-genome sequences, and we have yielded some fruitful results for the future research and surveillance of HFMD in China. Key messages HFMD epidemics in China have become a serious public health problem over the past decade. CV-A6 has surpassed EV-A71 and CV-A16 as the leading HFMD pathogen in most Chinese provinces.

scholarly journals Toward making sexual and gender diverse populations count in Australia

2020 ◽  
Vol 4 (2) ◽  
pp. 14-29
Author(s):  
Anthony Lyons ◽  
Joel Anderson ◽  
Mary Lou Rasmussen ◽  
Edith Gray
Keyword(s):  
Sexual Identity ◽  
Large Scale ◽  
Gender Diversity ◽  
Future Research ◽  
Diverse Populations ◽  
National Surveys ◽  
The Past ◽  
Gender Diverse ◽  
Social Support Services ◽  
And Gender

Background  Comprehensive data on gender and sexual identity is critical for the planning and delivery of health, education, and social support services. This paper examines ways in which sexual and gender diverse populations are being counted in research, with a view to informing discussions about how to represent these populations in future research. Aims  To examine approaches used for the collection of data from sexual and gender diverse populations in Australia. Data and methods  We reviewed nine examples of large national surveys conducted in Australia over the past ten years and compared the approaches used for collecting data on gender and sexual identity. Results  A diversity of approaches and a range of limitations were identified in how these diverse populations are counted. The proportions of survey respondents across sex, gender and sexual identity categories, and the types of categories, were also found to vary across studies. Conclusions  There is currently no consistent approach for collecting data involving sexual and gender diverse populations in Australia despite the need for large-scale surveys that reflect sexual and gender diversity. This paper identifies conceptual and methodological questions for consideration when planning how to capture diversity related to gender and sexual identity.

Sign in / Sign up

Export Citation Format

Share Document