Functionally graded structures of refractory metals by wire arc additive manufacturing

Marinelli, Gianrocco; Martina, Filomeno; Lewtas, Heather; Hancock, David; Ganguly, Saibal; Williams, Stewart

doi:10.1080/13621718.2019.1586162

Cited by 57 publications

(21 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It can be seen from the equation that the total value of J consists of an elastic and a plastic term, which are calculated using Equations ( 5) and ( 6), respectively. In these equations, K is the stress-intensity factor, which varies for different specimen geometries [29]; ν is the Poisson's ratio; a 0 is the initial crack length; A p is the plastic area under the load vs. LLD curve; and η is a geometry-dependent function, the solution of which, for the C (T) specimen geometry, is demonstrated in Equation (7).…”

Section: Crack Length Estimation and J-parameter Calculationmentioning

confidence: 99%

“…The new wire-arc additive manufacturing (WAAM) technique offers a variety of benefits for various industries. Compared with other additive manufacturing (AM) techniques, such as powder-based methods, WAAM is known for lower manufacturing costs and high deposition rates for large-scale structural fabrication, which leads to reduction in manufacturing lead time [4][5][6][7]. Nevertheless, this process consists of a pure welding mechanism, depositing one metal layer on top of another while constantly reheating and cooling down the built part.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Corrosion Effects on Fracture Toughness Properties of Wire Arc Additively Manufactured Low Carbon Steel Specimens

Ermakova

Mehmanparast

2022

Metals

View full text Add to dashboard Cite

The emerging wire + arc additive-manufacturing (WAAM) technique has significant potential to improve material design, as well as manufacturing cost and efficiency of structural components such as offshore wind turbines and subsequently reduce the levelised cost of energy (LCoE). Welded joints in offshore structures are usually considered potential spots for crack initiation due to the combination of high stress concentration at the weld toes, residual stresses introduced by the welding process and cyclic loading conditions in harsh, corrosive marine environments. The WAAM technique is a deposition method consisting of repetitive welding process that can be used as an alternative manufacturing technique for fabrication or repair of structural components. An important issue that needs to be understood in structural-integrity assessment of WAAM-built components is fracture-toughness behaviour. In particular, the sensitivity of fracture-toughness properties to corrosive environments must be examined in order to extend the application of the WAAM technique to offshore wind structures. Therefore, in this study, fracture-toughness tests were conducted on WAAM-built compact-tension specimens made of ER70S-6 and ER100S-1 steel that were initially exposed to a seawater corrosive environment prior to testing. All fracture-toughness tests were performed at room temperature, and crack length was estimated using the compliance method with a clip gauge attached onto the knife edge of the specimens. The obtained results, which include load vs. load-line displacement and J-integral vs. crack extension, were analysed and compared with the results of tests in air, without any exposure to seawater. The conclusions of this study show that corrosive environments affect the yield stress and R-curves of the selected materials and contribute to the overall understanding of the design requirements for functionally graded structures fabricated by means of WAAM technique for offshore applications.

show abstract

Section: Crack Length Estimation and J-parameter Calculationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Corrosion Effects on Fracture Toughness Properties of Wire Arc Additively Manufactured Low Carbon Steel Specimens

Ermakova

Mehmanparast

2022

Metals

View full text Add to dashboard Cite

show abstract

“…Automotive [11], Marine [115], Tools and molds [116] Nickel alloy [75] [ 117] [102,118] Inconel 718 [119], Inconel 625 [120] Aerospace [121], corrosion resistance [122], high temperature [123] Refractories [124] Tungsten [49], Molybdenum [124], Tantalum [124] Nuclear , Heat exchanger [124] Other CuSi3 [125], Bronze [126], Invar [116], Shape memory alloy [127] In summary, it has been observed that, in most of the research, a straight wall has been fabricated using WAAM and samples have been taken out from it to carry out the microstructural analysis and mechanical tests to determine its mechanical properties such as tensile strength, hardness, toughness, etc.…”

Section: Dissimilar Alloymentioning

confidence: 99%

Wire Arc Additive Manufacturing: A Comprehensive Review and Research Directions

Raut

Taiwade

2021

J. of Materi Eng and Perform

View full text Add to dashboard Cite

Over the past years, the demand for the wire arc additive manufacturing (WAAM) is potentially increased, and it has become a promising alternative to subtractive manufacturing. Research reported that the wire arc additively manufactured (WAAMed) materialÕs mechanical properties are comparable to wrought or cast material. In comparison with other fusion sources, WAAM offers a significant cost saving and a higher deposition rate. However, there are significant challenges associated with WAAM such as undesirable microstructures and mechanical properties, high residual stresses, and distortion. Thus, more research is still needed to handle the above challenges by optimizing the process parameters and post-deposition heat treatment. In line with the above, this paper attempts to fill the gap by presenting a comprehensive review of WAAM literature including stagewise development of WAAM, metals and alloys used, effects of process parameters, methodologies used by various researchers to improve the quality of WAAM component. Besides, this work proposes the areas that could be used as avenues for future research.

show abstract

“…The WAAM process has successfully produced large-scale parts in stainless steel [8], Inconel ® [9], titanium [10], aluminium [11] and tungsten [12]. Furthermore, functionally graded structures of refractory metals have also been deposited using WAAM [13]. The manufacture of large and engineered components by WAAM is attractive also because of the low system and operating costs, as well as the modularity of the system design [6,14].…”

Section: Introductionmentioning

confidence: 99%

Grain refinement in an unalloyed tantalum structure by combining Wire+Arc additive manufacturing and vertical cold rolling

Marinelli

Martina

Ganguly

et al. 2020

Additive Manufacturing

View full text Add to dashboard Cite

Components manufactured via Wire + Arc Additive Manufacturing are usually characterised by large columnar grains. This can be mitigated by introducing in-process cold-rolling; in fact, the associated local plastic deformation leads to a reduction of distortion and residual stresses, and to microstructural refinement. In this research, interpass rolling was applied with a load of 50 kN to a tantalum linear structure to assess its effectiveness in changing the grain structure from columnar to equiaxed, as well as in refining the grain size. An average grain size of 650 µm has been obtained after five cycles of inter-pass rolling and deposition. When the deformed layer was reheated during the subsequent deposition, recrystallisation occurred, leading to the growth of new strain-free finer equiaxed grains. The depth of the refined region has been characterised and correlated to the hardness profile developed after rolling. A reduction of porosity was also registered. Furthermore, a random texture was formed after rolling, which should result in isotropic mechanical properties. Wire + Arc Additive Manufacturing process demonstrated the ability to deposit sound refractory metal components and the possibility to improve the microstructure when coupled with cold inter-pass rolling.

show abstract

Functionally graded structures of refractory metals by wire arc additive manufacturing

Cited by 57 publications

References 35 publications

Corrosion Effects on Fracture Toughness Properties of Wire Arc Additively Manufactured Low Carbon Steel Specimens

Corrosion Effects on Fracture Toughness Properties of Wire Arc Additively Manufactured Low Carbon Steel Specimens

Wire Arc Additive Manufacturing: A Comprehensive Review and Research Directions

Grain refinement in an unalloyed tantalum structure by combining Wire+Arc additive manufacturing and vertical cold rolling

Contact Info

Product

Resources

About