Optimizing Cutting Planes for Advanced Joining and Additive Manufacturing

Author(s):  
Brandon Massoni ◽  
Matthew I. Campbell

While additive manufacturing allows more complex shapes than conventional manufacturing processes, there is a clear benefit in leveraging both new and old processes in the definition of metal parts. For example, one could create complex part shapes where the main “body” is defined by extrusion and machining, while small protruding features are defined by additive manufacturing. This paper looks at how optimization and geometric reasoning can be combined to identify cutting planes within complex three-dimensional (3D) shapes. These cutting planes are used to divide realistic mechanical parts into subparts that can be joined together through additive manufacturing or linear friction welding (LFW). The optimization method presents possible manufacturing alternatives to an engineering designer where optimality is defined as a minimization of cost. The paper presents and compares several cutting planes identification methods and describes how the optimization finds the optimal results for several example parts.

Author(s):  
Brandon Massoni ◽  
Matthew I. Campbell

While additive manufacturing allows more complex shapes than conventional manufacturing processes, there is a clear benefit in leveraging both new and old processes in the definition of new parts. For example, one could create complex part shapes where the main “body” is defined by extrusion and machining, while small protruding features are defined by additive manufacturing. This paper looks at how optimization and geometric reasoning can be combined to identify optimal separation planes within a complex three-dimensional shapes. These separations indicate the joining processes in reverse. The optimization method presents possible manufacturing alternatives to an engineering designer where optimality is defined as a minimization of cost. The process identifies the cutting planes as well as the combination of processes required to join the individual parts together. The paper presents several examples of complex shapes and describes how the optimization finds the optimal results.


2019 ◽  
Vol 25 (10) ◽  
pp. 1637-1646 ◽  
Author(s):  
Bohao Xu ◽  
Xiaodong Tan ◽  
Xizhi Gu ◽  
Donghong Ding ◽  
Yuelin Deng ◽  
...  

Purpose Once an uneven substrate is aligned, traditional control theories and methods can be used on it, so aligning is of great significance for the development of wire and arc additive manufacturing (WAAM). This paper aims to propose a shape-driven control method for aligning a substrate with slopes to expand the application of WAAM. Design/methodology/approach A substrate with slopes must be aligned by depositing weld beads with slopes. First, considering the large height differences of slopes, multi-layer deposition is needed, and the number of layer of weld beads must be ascertained. Second, the change in the deposition rate is controlled as a ramp function to generate weld beads with slopes. Third, the variation of the deposition rate must be fine-tuned to compensate for the deviation between the actual and theoretical layer heights at the deposition of each layer. Finally, the parameters of the ramp functions at the deposition of each layer are determined through an optimization method. Findings First, to model the response function of layer height to deposition rate, the experiments are conducted with the deposition rate jumping from 4 to 8 mm/s and from 8 to 4 mm/s. When the deposition rate jumps from 4 to 8 mm/s and from 8 to 4 mm/s, the difference in the height of each layer decreases as the number of layer increases. Second, the variation of the deposition rate can be fine-tuned based on the deviation between the measured and theoretical layer heights because the variation of the deposition rate is proportional to the layer height when the initial and end deposition rates are near 4 or 8 mm/s, respectively. Third, the experimental results demonstrate that the proposed method is effective for single-layer aligning and aligning a substrate with one or more slopes. Originality/value The proposed method can expand the application of WAAM to an uneven substrate with slopes and lays the foundation for aligning tasks focused on uneven substrates with more complex shapes.


2019 ◽  
Vol 11 (8) ◽  
pp. 168781401985978
Author(s):  
Enrico Boccini ◽  
Rocco Furferi ◽  
Lapo Governi ◽  
Enrico Meli ◽  
Alessandro Ridolfi ◽  
...  

Used in several industrial fields to create innovative designs, topology optimization is a method to design a structure characterized by maximum stiffness properties and reduced weights. By integrating topology optimization with additive layer manufacturing and, at the same time, by using innovative materials such as lattice structures, it is possible to realize complex three-dimensional geometries unthinkable using traditional subtractive techniques. Surprisingly, the extraordinary potential of topology optimization method (especially when coupled with additive manufacturing and lattice structures) has not yet been extensively developed to study rotating machines. Based on the above considerations, the applicability of topology optimization, additive manufacturing, and lattice structures to the fields of turbomachinery and rotordynamics is here explored. Such techniques are applied to a turbine disk to optimize its performance in terms of resonance and mass reduction. The obtained results are quite encouraging since this approach allows improving existing turbomachinery components’ performance when compared with traditional one.


2020 ◽  
pp. 52-85
Author(s):  
Leonardo Frizziero ◽  
Giampiero Donnici ◽  
Alfredo Liverani ◽  
Karim Dhaimini

In an increasingly competitive business world, the “time to market” of products has become a key factor for business success. There are different techniques that anticipate design mistakes and launch products on the market in less time. Among the most used methodologies in the design and definition of the requirements, quality function deployment (QFD) and design for Six Sigma (DFSS) can be used. In the prototyping phase, it is possible to address the emerging technology of additive manufacturing. Today, three-dimensional printing is already used as a rapid prototyping technique. However, the real challenge that industry is facing is the use of these machineries for large-scale production of parts, now possible with new HP multi-fusion. The aim of this article is to study the entire product development process taking advantage of the most modern models and technologies for the final realization of a case study that involves the design and prototyping of an innovative multifunctional fan (lamp, aroma diffuser and fan) through the Multi Jet Fusion of HP. To begin with, issues related to the DFSS, the QFD and their application to identify the fan requirements are explored. Once the requirements have been defined, the modern CAD design systems and the CAE systems for the validation of the case study will be analyzed and applied. Finally, HP's Multi Jet Fusion methodology and design rules for additive manufacturing will be analyzed in detail, trying to exploit all the positive aspects it offers.


Sensors ◽  
2020 ◽  
Vol 20 (2) ◽  
pp. 470
Author(s):  
Gianluca Barile ◽  
Alfiero Leoni ◽  
Mirco Muttillo ◽  
Romina Paolucci ◽  
Gianfranco Fazzini ◽  
...  

The three-dimensional printing of complex shapes without using supporting structures is the most attractive factor of merit in current additive manufacturing because it allows to drastically reduce printing time, and ideally nullify postprocessing and waste material. In this work, we present an innovative procedure and algorithm (Print on Air, PoA) for additive manufacturing that, relying on sensing systems embedded into the three-dimensional (3D) printer (e.g., temperature and speed sensors), aims at generating a printing sequence capable of a self-sustaining bridge and overhang structures. This feature was achieved by splitting the actual floating area of the layer where the aforementioned structures are in many subsections. Each is generated with a negligible floating surface and printed in a well-determined sequence with accurate temperature and speed profiles. Therefore, each subsection is formed without the need for scaffolding, simultaneously acting as a supporting structure for the following subsection. The array of subsections constitutes the actual bridge or overhang structure. The proposed method can be used for any object, including very long bridges or convex surfaces. The revolutionary method is here reported and evaluated in order to show its applicability in any condition. Although the study was conducted in a Fused Deposition Material (FDM) environment, it can certainly be adapted to other manufacturing environments with adequate modifications.


2021 ◽  
pp. 126-132
Author(s):  
Iryna Malinovska

Formulation of the problem. The article is devoted to the classification of copyright objects. Researchers' views on the division of different works into relevant types and groups are analyzed. It is emphasized that copyright objects are in constant dynamics, due to globalization, development of scientific and technological progress, social networks. Recent research on the topic. The characteristics of copyright objects were addressed by the same researchers as O.E. Abramov, I.I. Vishchynets, O.V. Zhilinkova. O.O. Odintsova. O.O. Shtefan, R.B. Shishka, N.E. Yarkina. M.M. Yasharova, etc. Despite their contribution to the development of the concept of the object of copyright, an updated study of the classification of copyrighted objects by them is not offered in full. The purpose. To investigate and analyse the characteristics and features of copyrighted objects, to distinguish their common and distinctive features that are important for the classification of copyrighted objects. Article’s main body. It was established that for the objects of copyright remains unchanged what they are: should be the result of human creative activity; have novelty, originality, as inherent properties of creativity; characterized by fixation, which at the same time should be static, which complicates further changes to the object; free from the structure of the content, which can be varied in its content; objects regardless of the fact of publication. It is noted that there are changes in the legislation of Ukraine on expanding the list of copyright objects. Separately, the issue of original and derivative works was investigated. Certain feature of composite works. It is noted that the definition of the original work and its inherent features in the Law is important in terms of ensuring a unified systematic approach to law enforcement activities for both derivative works and part (title) of the work. On the basis of the above proposed the following classification of copyright objects: depending on the creative nature of the work, copyright objects may be divided into: original (created exclusively in the form of personal creative contribution of the author) and derivative works (creativity consists in searching, combining the creative achievements of other authors); in the objective form of expression: oral, written, electronic, three-dimensional; according to the criterion of the internal content of the work: simple (covering structurally one object) and complex (may consist of different objects of copyright); depending on the characteristics of the processing of the original work: objects of holistic processing of works and objects of partial processing (processing of excerpts of various works); depending on the nature of financial support, copyright objects may be divided into: objects created on the basis of state order, created on the basis of private orders or financed personally by the author at will; depending on the possibility of distinguishing homogeneous elements of the work into: dividing and indivisible works.


Author(s):  
Robert D. Nelson ◽  
Sharon R. Hasslen ◽  
Stanley L. Erlandsen

Receptors are commonly defined in terms of number per cell, affinity for ligand, chemical structure, mode of attachment to the cell surface, and mechanism of signal transduction. We propose to show that knowledge of spatial distribution of receptors on the cell surface can provide additional clues to their function and components of functional control.L-selectin and Mac-1 denote two receptor populations on the neutrophil surface that mediate neutrophil-endothelial cell adherence interactions and provide for targeting of neutrophil recruitment to sites of inflammation. We have studied the spatial distributions of these receptors using LVSEM and backscatter imaging of isolated human neutrophils stained with mouse anti-receptor (primary) antibody and goat anti-mouse (secondary) antibody conjugated to 12 nm colloidal gold. This combination of techniques provides for three-dimensional analysis of the expression of these receptors on different surface membrane domains of the neutrophil: the ruffles and microvilli that project from the cell surface, and the cell body between these projecting structures.


Author(s):  
Sandra Regina Marchi ◽  
Maria Lucia Okimoto ◽  
ALESSANDRO MARQUES ◽  
Ramón Sigifredo Cortés Paredes ◽  
Rafael Lima Vieira

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Min Yang ◽  
Lu Wang ◽  
Wentao Yan

AbstractA three-dimensional phase-field model is developed to simulate grain evolutions during powder-bed-fusion (PBF) additive manufacturing, while the physically-informed temperature profile is implemented from a thermal-fluid flow model. The phase-field model incorporates a nucleation model based on classical nucleation theory, as well as the initial grain structures of powder particles and substrate. The grain evolutions during the three-layer three-track PBF process are comprehensively reproduced, including grain nucleation and growth in molten pools, epitaxial growth from powder particles, substrate and previous tracks, grain re-melting and re-growth in overlapping zones, and grain coarsening in heat-affected zones. A validation experiment has been carried out, showing that the simulation results are consistent with the experimental results in the molten pool and grain morphologies. Furthermore, the grain refinement by adding nanoparticles is preliminarily reproduced and compared against the experimental result in literature.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xiaoyu Zhao ◽  
Ye Zhao ◽  
Ming-De Li ◽  
Zhong’an Li ◽  
Haiyan Peng ◽  
...  

AbstractPhotopolymerization-based three-dimensional (3D) printing can enable customized manufacturing that is difficult to achieve through other traditional means. Nevertheless, it remains challenging to achieve efficient 3D printing due to the compromise between print speed and resolution. Herein, we report an efficient 3D printing approach based on the photooxidation of ketocoumarin that functions as the photosensitizer during photopolymerization, which can simultaneously deliver high print speed (5.1 cm h−1) and high print resolution (23 μm) on a common 3D printer. Mechanistically, the initiating radical and deethylated ketocoumarin are both generated upon visible light exposure, with the former giving rise to rapid photopolymerization and high print speed while the latter ensuring high print resolution by confining the light penetration. By comparison, the printed feature is hard to identify when the ketocoumarin encounters photoreduction due to the increased lateral photopolymerization. The proposed approach here provides a viable solution towards efficient additive manufacturing by controlling the photoreaction of photosensitizers during photopolymerization.


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