Pages
- 1
- 2
- document
-
Baqershahi, Mohammad Hassan (author), Ayas, C. (author), Ghafoori, Elyas (author)Wire arc additive manufacturing (WAAM) enables the manufacturing of efficient and lightweight structural elements in which material can be utilised wherever needed in an optimised shape, in contrast to standard prismatic profiles used in construction. However, the specific energy consumption (SEC) of WAAM is higher than that of conventional...journal article 2024
- document
-
Ranjan, R. (author), Langelaar, Matthijs (author), van Keulen, A. (author), Ayas, C. (author)Computational process modelling of metal additive manufacturing has gained significant research attention in recent past. The cornerstone of many process models is the transient thermal response during the AM process. Since deposition-scale modelling of the thermal conditions in AM is computationally expensive, spatial and temporal...journal article 2023
- document
-
Bayat, Mohamad (author), Zinovieva, Olga (author), Ferrari, Federico (author), Ayas, C. (author), Langelaar, Matthijs (author), Spangenberg, Jon (author), Salajeghe, Roozbeh (author), Poulios, Konstantinos (author), Mohanty, Sankhya (author), Sigmund, Ole (author), Hattel, Jesper (author)Additive manufacturing (AM) processes have proven to be a perfect match for topology optimization (TO), as they are able to realize sophisticated geometries in a unique layer-by-layer manner. From a manufacturing viewpoint, however, there is a significant likelihood of process-related defects within complex geometrical features designed by TO...review 2023
- document
-
Macallister, N. (author), Chellu, Sreyas (author), Riemslag, A.C. (author), Scott, S.P. (author), Ayas, C. (author), Popovich, V. (author), Becker, Thorsten Hermann (author)Sub-size specimen testing offers a potentially elegant solution to accompany fatigue life assessments in determining vital fatigue parameters such as effective fatigue crack growth propagation thresholds (ΔK<sub>th,eff</sub>). Additively manufactured parts stand to benefit from this in potential build-by-build fatigue validation without...journal article 2023
- document
-
Mishra, V. (author), Ayas, C. (author), Langelaar, Matthijs (author)In metal Additive Manufacturing (AM), the deposited material is subjected to a series of heating and cooling cycles. The locally occurring temperature extremes and cooling rates determine solid-state phase fractions, material microstructure, texture, and ultimately the local material properties. As the shape of a part determines the local...journal article 2023
- document
-
Mishra, V. (author), Babu, A. (author), Schreurs, R. (author), Wu, K. (author), Hermans, M.J.M. (author), Ayas, C. (author)Wire and Arc Additive Manufacturing (WAAM) emerged as a manufacturing process for large scale structures with extensive form and design freedom. WAAM can be fully exploited once the relation between the transient thermal history and its relation to microstructure development and resultant mechanical properties is established. This relation...journal article 2023
- document
-
Ranjan, R. (author), Chen, Z. (author), Ayas, C. (author), Langelaar, Matthijs (author), van Keulen, A. (author)Overheating is a major issue especially in metal Additive Manufacturing (AM) processes, leading to poor surface quality, lack of dimensional precision, inferior performance and/or build failures. A 3D density-based topology optimization (TO) method is presented which addresses the issue of local overheating during metal AM. This is achieved...journal article 2023
- document
-
Ranjan, R. (author), Ayas, C. (author), Langelaar, Matthijs (author), van Keulen, A. (author)A novel constraint to prevent local overheating is presented for use in topology optimization (TO). The very basis for the constraint is the Additive Manufacturing (AM) process physics. AM enables fabrication of highly complex topologically optimized designs. However, local overheating is a major concern especially in metal AM processes...journal article 2022
- document
-
Irani, N. (author), Murugesan, Yaswanth (author), Ayas, C. (author), Nicola, L. (author)Discrete dislocation plasticity is a modeling technique that treats plasticity as the collective motion of dislocations. The dislocations are described through their elastic Volterra fields, outside of a cylindrical core region, with a few Burgers vectors of diameter. The contribution of the core fields to the dislocation dynamics is...journal article 2022
- document
-
Mishra, V. (author), Ayas, C. (author), Langelaar, Matthijs (author), van Keulen, A. (author)A remarkable elastic anisotropy in plates of austenitic stainless steel produced by the Wire and Arc Additive Manufacturing process is recently reported. The Young's modulus depends on the angle of orientation with respect to the material deposition direction. Here, for the first time, this anisotropy is exploited to maximize structural...journal article 2022
- document
-
Zhang, Z. (author), Peeters, J.W.R. (author), Popovich, V. (author), Ayas, C. (author)Hydrogen plays a vital role in the utilisation of renewable energy, but ingress and diffusion of hydrogen in a gas turbine can induce hydrogen embrittlement on its metallic components. This paper aims to investigate the hydrogen transport in a non-hydride forming alloy such as Alloy 690 used in gas turbines inspired by service conditions of...journal article 2022
- document
-
Mishra, V. (author), Ayas, C. (author), Langelaar, Matthijs (author), van Keulen, A. (author)Topology optimization typically generates designs that exhibit significant geometrical complexity, which can pose difficulties for manufacturing and assembly. The number of occurrences of an important design feature, in particular intersections, increases with geometrical complexity. Intersections are essential for load transfer in many...journal article 2022
- document
-
Gençog̃lu, C. (author), Tekog̃lu, C. (author), Ayas, C. (author)The effects of five different types of imperfection (fractured cell walls, missing cells, cell wall waviness, cell wall misalignment, and non-uniform cell wall thickness) on actuation performance are numerically investigated for the Kagome lattice and two of its variants: Double Kagome (DK) and Kagome with concentric triangles (KT). The...journal article 2022
- document
-
Yang, Y. (author), Zhou, Xin (author), Li, Quan (author), Ayas, C. (author)Residual stresses and distortions are major obstacles against the more widespread application of wire arc additive manufacturing. Since the steep temperature gradients due to a moving localised heat source are inevitable in this process, accurate prediction of the thermally induced residual stresses and distortions is of paramount importance....journal article 2021
- document
-
van de Ven, E.A. (author), Maas, Robert (author), Ayas, C. (author), Langelaar, Matthijs (author), van Keulen, A. (author)Although additive manufacturing (AM) allows for a large design freedom, there are some manufacturing limitations that have to be taken into consideration. One of the most restricting design rules is the minimum allowable overhang angle. To make topology optimization suitable for AM, several algorithms have been published to enforce a minimum...journal article 2021
- document
-
Fernández, E. (author), Ayas, C. (author), Langelaar, Matthijs (author), Duysinx, P. (author)Additive Manufacturing (AM) processes intended for large-scale components deposit large volumes of material to shorten process duration. This reduces the resolution of the AM process, which is typically defined by the deposition nozzle size. If the resolution limitation is not considered when designing for Large-Scale Additive Manufacturing ...journal article 2021
- document
-
Misiun, Grzegorz (author), van de Ven, E.A. (author), Langelaar, Matthijs (author), Geijselaers, Hubert (author), van Keulen, A. (author), van den Boogaard, Ton (author), Ayas, C. (author)An important cause of failure in powder bed additive manufacturing is the distortion of the part due to thermal shrinkage during printing and the relaxation of residual stresses after its release from the base plate. In this paper, Additive Manufacturing simulations are coupled with Topology Optimization in order to generate designs that are...journal article 2021
- document
-
Zhang, Z. (author), Ayas, C. (author), Popovich, V. (author), Peeters, J.W.R. (author)In this paper, a finite element (FE) model is developed to investigate lattice hydrogen diffusion in a solid metal under the influence of stress and temperature gradients. This model is applied to a plate with a circular hole which is subjected to temperature and hydrogen concentration gradients. It is demonstrated that temperature gradients...journal article 2021
- document
-
van de Ven, E.A. (author), Ayas, C. (author), Langelaar, Matthijs (author), Maas, Robert (author), van Keulen, A. (author)Additive manufacturing (AM) and topology optimization (TO) have a synergetic relation, as AM can produce complex TO designs, and TO provides high-performance parts that utilize the form freedom provided by AM. Recently, TO has been tailored more toward AM with the inclusion of the minimum allowable overhang angle as a design constraint:...journal article 2021
- document
-
Yang, Y. (author), van Keulen, A. (author), Ayas, C. (author)Selective laser melting (SLM) is a widely used additive manufacturing method for building metal parts in a layer-by-layer manner thereby imposing almost no limitations on the geometrical layout of the part. The SLM process has a crucial impact on the microstructure, strength, surface quality and even the shape of the part, all of which depend on...journal article 2020
Pages
- 1
- 2