Additive Manufacturing Capabilities Research Articles

Experimental investigation of an additively manufactured cold plate for multi-chip module cooling generated using the homogenization approach to topology optimization

The homogenization approach to topology optimization is promising for generating high-performance, liquid-cooled cold plates due to its ability to create sub-resolution features by optimizing the spatial distribution and porosities of physical microstructures. This optimization capability has been demonstrated for the design of compact microchannel heat sinks under uniform heating conditions. However, there is a need to understand its applicability for practical applications involving complex boundary conditions posed by modern electronics packaging requirements. This work performs the topology optimization, design for manufacturing, fabrication, and experimental testing of a liquid-cooled cold plate for an application-representative multi-chip module with eight devices. The cold plate design requirements and boundary conditions involve eight equally spaced heat generating sources and liquid inlet/outlet ports that are off-center, introducing flow distribution challenges to the thermal design. A topology optimization algorithm is developed using the homogenization approach with circular pin fins chosen as the microstructure. An empirical permeability correlation for pin fins is developed which is implemented in the porous media flow model of the topology optimization algorithm to simulate pressure drop across additively manufactured pin fins. In addition to the topology optimized designs, a benchmark cold plate design with uniformly distributed 1.2 mm diameter pin fins, representative of the feature dimensions currently adopted in applications for the investigated boundary conditions, is also evaluated. Comparison of the topology optimized cold plate generated using the design freedom brought by additive manufacturing to the benchmark design highlights the optimizer’s ability to uniformly distribute the coolant amongst the heated regions. The maximum base temperature rise is 35.5 °C for the benchmark design versus 6.6 °C for the topology optimized design. Flow uniformity combined with the high convective heat transfer of the sub-resolution fins and channels in the vicinity of the heated regions keep the device temperatures low. The topology optimized cold plate is additively manufactured and experimentally tested at various flow rates. The experimental results match well with the model predictions, with a mean absolute percentage error of 5.5 % and 9.7 % for pressure drop and thermal resistance respectively, indicating that the optimal performance promised by the algorithm can be realized using additively manufactured parts. The work presented here demonstrates the overall process flow for the homogenization approach in leveraging the capabilities of additive manufacturing to generate high-performance liquid cold plates for practical applications.

Facilitating the Production of 3D-Printed Spare Parts in the Design of Plastic Parts: A Design Requirement Review

Using additive manufacturing for spare part production can ensure that spare parts are available for a long time. However, spare parts are currently not designed for additive manufacturing. This study aimed to find how the production of 3D-printed spare parts can be facilitated in the design of plastic parts. We used a literature review and illustrative case to find how the design requirements for standard injection moulded plastic parts relate to the manufacturing capabilities of additive manufacturing for spare parts. The design requirements were defined by assigning corresponding structural and material properties. These requirements were then used to construct and evaluate the capabilities of additive manufacturing compared to injection moulding. It was found that additive manufacturing is especially suitable for requirements like Accuracy, Heat resistance, and Chemical resistance. However, to fully enable 3D-printed spare parts, certain design challenges still need to be tackled. Designers should pay careful attention to the synergies and trade-offs between design requirements and the challenges that might arise from the combination of certain requirements. Also, designers should ensure products are easily reparable before considering 3D-printed spare parts. If we target these challenges in the design phase, we can facilitate 3D-printed spare parts that enable product repairability.

Preparation of high-tensile-ductility and high-conductivity alumina dispersion-strengthened copper via a cold spray additive manufacturing-friction stir processing composite process

The solid-state forming capabilities of cold spray additive manufacturing (CSAM) offer a new method for creating nano-reinforced materials. However, the interface of the deposits often fails to form strong metallurgical bonds, leading to mechanical defects that weaken the material. This study investigates the preparation of highly plastic nano-alumina dispersion-strengthened copper by combining CSAM with friction stir processing (FSP), both solid-state techniques. The results show that FSP treatment fuses the interfaces of the deposited particles, transforming the microstructure from multi-scale, elongated grains to a uniform ultrafine-grained (UFG) structure. The average grain size reduces from 3.1 μm to 0.86 μm, and the proportion of high-angle grain boundaries increases from 42.5 % to 85.2 %. This treatment significantly enhances both mechanical and electrical properties. The ultimate tensile strength increases from 210 MPa to 450 MPa, elongation at break improves from 1 % to 35 %, and electrical conductivity rises from 70 % IACS to 81 % IACS. These findings demonstrate the potential of the combined CSAM-FSP approach for producing high-performance nano-alumina dispersion-strengthened copper with superior mechanical and electrical properties.

Polymer-based 3D printing of function-integrated optomechanics – design guidelines and system evaluation

PurposeThis study aims to extend the known design guidelines for the polymer-based fused filament fabrication (FFF) 3D printing process with the focus on function-integrated components, specifically optomechanical parts. The potential of this approach is demonstrated by manufacturing function-integrated optomechanics for a low-power solid-state laser system.Design/methodology/approachFor the production of function-integrated additively manufactured optomechanics using the FFF process, essential components and subsystems have been identified for which no design guidelines are available. This includes guidelines for integrating elements, particularly optics, into a polymer structure as well as guidelines for printing functional threads and ball joints. Based on these results, combined with prior research, a function-integrated low-power solid-state laser optomechanic was fabricated via the FFF process, using a commercial 3D printer of the type Ultimaker 3. The laser system's performance was assessed and compared to a reference system that employed commercial optomechanics, additionally confirming the design guidelines derived from the study.FindingsBased on the design goal of function integration, the existing design guidelines for the FFF process are systematically extended. This success is demonstrated by the fabrication of an integrated optomechanic for a solid-state laser system.Practical implicationsBased on these results, scientists and engineers will be able to use the FFF process more extensively and benefit from the possibilities of function-integrated manufacturing.Originality/valueExtensive research has been published on additive manufacturing of optomechanics. However, this research often emphasizes only cost reduction and short-term availability of components by reprinting existing parts. This paper aims to explore the capabilities of additive manufacturing in the production of function-integrated components to reduce the number of individual parts required, thereby decreasing the workload for system assembly and leading to an innovative production process for optical systems. Consequently, where needed, it provides new design guidelines or extends existing ones and verifies them by means of test series.

Critical condition for initiation of dynamic recrystallisation in electron beam powder bed fused Ti-6Al-4 V Alloy

Despite the unique capabilities of Additive Manufacturing (AM) processes for producing Ti components with complex geometries, the desired properties are only achievable if a holistic scheme is devised, considering the synergistic role of post-processing steps. This work aimed to enhance the applicability of metal AM products by improving the process chain in the manufacturing industry. For this purpose, the current work demonstrates a comprehensive investigation into the hot deformation of Ti-6Al-4 V (Ti64) pre-forms produced via the Electron Beam Powder Bed Fusion (EB-PBF) process focusing on the determination of critical conditions for initiating Dynamic Recrystallization (DRX) in these components. Following a sequential evaluation procedure, hot deformation experiments were carried out at temperatures ranging from 1000 to 1200 °C and strain rates of 0.001–1 s−1 to determine the critical stress and strain required for initiating DRX in Ti64 pre-forms and compare them to their wrought counterparts. In addition, a specific Finite Element Model (FEM) was coupled with DRX kinetics equations to predict the volume percentage of DRX grains during the hot deformation of the pre-forms. The analysis of flow stress curves showed a significant peak stress at low strains, which is then followed by a period of flow softening and eventually transitions into a nearly steady-state flow at higher strains. In addition, compared to their wrought counterparts, the EB-PBF samples exhibited a significantly superior flow softening behavior, as evidenced by a more significant volume fraction of DRX and faster recrystallisation rates. It was also revealed that the normalised strain for DRX initiation in the EB-PBF Ti64 and wrought one was 0.55 and 0.67, respectively. FEM results closely matched the experimental finding, confirming its reliability in providing valuable insights into microstructural evolution and offering a time-efficient alternative for process design and property optimisation, lowering dependence on trial-and-error approaches. Through a combination of experiments, numerical analysis, and finite element simulations, this study sheds light on the macroscopic deformation and microstructural transformations occurring during hot working processes.

Additive Manufacturing of Composite Materials and Functionally Graded Structures Using Archerfish Hunting Technique

ABSTRACTThis paper proposes an optimisation method for fabricating composite materials and functionally graded structures. Using the proposed method, 3D printing of copper (Cu)–polyethylene (PE) composite, Al2O3–ZrO2 ceramic composite and functionally graded CuO foams are utilised. This work aims to advance the capabilities of additive manufacturing by leveraging nature‐inspired approaches to create complex, tailored structures with enhanced performance across various industries. The major objective of the proposed method is to reduce the feed rate and increase the airflow rate and airflow temperature for the heat transfer process. Using the proposed technique in the advanced preparation conditions, Cu–PE composites with unreliable Cu substances are fabricated. The PE binder particle is melting as well as forming thick composites by means of soft surfaces. Using the proposed AHO approach, functionally graded materials with common distributions can be efficiently optimised. By then, the proposed model is implemented on the MATLAB platform, and its execution is calculated using the current procedures. The proposed technique displays superior outcomes in all existing methods like wild horse optimiser, particle swarm optimisation and heap‐based optimiser. The proposed method shows a throughput of 57 mm3. The existing method shows the throughput of 32, 27 and 45 mm3. The results show that the proposed method has higher throughput compared with existing methods.

Effect of the building orientation on additively manufactured copper alloy: Hydraulic performance of different surface roughness channels

The additive manufacturing capabilities open new frontiers in the design of complex geometries in many different application fields, especially thermal science, in which multi-functional, efficient, compact components with internal cooling or heating channels are becoming more and more requested. Among the possible additive manufacturing technologies, the laser powder bed fusion process has recently been proven to manufacture high-conductivity metals, with good mechanical and thermal properties (i.e. pure copper and copper alloys), attracting the attention of the heat transfer community. However, depending on the material, design, and process parameters, the surface roughness of the components can remarkably change and become a critical issue in cooling applications. Currently, the surface texture characteristics and the final channel size cannot be accurately estimated a priori, and thus the initial hypothesis of the current design methods may lead to unpredictable and undesired results. This work experimentally and numerically explores the effects of the building orientation on the fluid dynamic behaviour in CuCrZr alloy channels, which is considered one of the most promising additive manufacturing materials for thermal applications. By coupling the experimental hydraulic results with surface characterization and X-ray computer tomography dimensional measurements of the channels, a novel simplified methodology to properly correlate the pressure drop to the surface texture of a single wall is proposed and numerically validated.

Shear-thickening-fluid-based meta-material for adaptive impact response

Lattice and Triply-Periodic-Minimal-Surface (TPMS) structures are widely employed in different engineering disciplines, combining interesting designs with optimal mechanical properties thanks to the capabilities of Additive Manufacturing. In this framework, a technique based on filling a 3D-printed flexible structure with a shear-thickening fluid (STF) is proposed to improve the mechanical response of the resulting bi-phase composite under impact loads in the low-velocity regime up to around 3 m/s. Test data indicate that once the critical shear rate threshold for the fluid is reached, the STF-filled structure can effectively smooth the peak acceleration by 50%, decrease the penetration depth and significantly enhance the energy absorption capability by a remarkable 85%. The proposed hybrid composite paves the way to novel functional applications, exploiting the adaptive behavior of non-Newtonian fillers. To this end, a Finite-Element model is proposed to further investigate and optimize the underlying fluid-structure interaction responsible for improvement of the dynamic compressive response.

3D volume construction methodology for cold spray additive manufacturing

Cold spraying has proved as an attractive and rapidly developing solid-state material deposition process that allows for fast formation of high quality, large 3D volume objects. Low risks of undesirable heat effects lead to increased interest in cold spraying based rapid additive manufacturing. However, by continuous powder spraying and high-pressure gas operation, cold spray additive manufacturing in terms of shape building is sensitive to operating parameters and imposes high requirements on the control of process conditions and locally needed kinematics. Every step of the manufacturing process therefore needs to be meticulously conceived and planned, especially the toolpath planning and implementation. This is not only essential to meet basic performance requirements, but also needed for the desired geometric accuracy. To address these needs, this study presents a new implementation method for cold spray additive manufacturing to improve manufacturing accuracy and flexibility. The workflow and principles of the proposed method are explained and strategies are presented for building up various component types, including rotational geometries as well as freestanding parts. The developed algorithms for 3D applications can be well integrated into the cold spray additive manufacturing process for toolpath planning and path parameter determination. Reliable and accurate robot programs were developed to make the process easy to repeat and to follow. Toolpath planning and robot programming are supported and performed by applying virtual cells to simulate the automation process for the real scenario. Path parameter adjustment and kinematic optimization can then be conducted according to the feedback from the simulation result. Applied benchmarking tests prove acceptable shape accuracy and demonstrate that the current method can enhance the capabilities of cold spray additive manufacturing for near-net shape construction. This implies that careful planning and manufacturing strategies should enable overcoming the challenges associated with cold spray additive manufacturing.

Nozzle Innovations That Improve Capacity and Capabilities of Multimaterial Additive Manufacturing.

Multimaterial additive manufacturing incorporates multiple species within a single 3D-printed object to enhance its material properties and functionality. This technology could play a key role in distributed manufacturing. However, conventional layer-by-layer construction methods must operate at low volumetric throughputs to maintain fine feature resolution. One approach to overcome this challenge and increase production capacity is to structure multimaterial components in the printhead prior to deposition. Here we survey four classes of multimaterial nozzle innovations, nozzle arrays, coextruders, static mixers, and advective assemblers, designed for this purpose. Additionally, each design offers unique capabilities that provide benefits associated with accessible architectures, interfacial adhesion, material properties, and even living-cell viability. Accessing these benefits requires trade-offs, which may be mitigated with future investigation. Leveraging decades of research and development of multiphase extrusion equipment can help us engineer the next generation of 3D-printing nozzles and expand the capabilities and practical reach of multimaterial additive manufacturing.

Single-step fully 3D printed and co-sintered solid oxide fuel cells

The capabilities of hybrid multi-material additive manufacturing to produce entire self-standing SOFC devices have been proved in just two stages, 3D printing and co-sintering.

The Current Design for Additive Manufacturing Research Frontier

Design for additive manufacturing (DFAM) seeks to develop designs that take advantage of the unique capabilities of additive manufacturing (AM) processes to maximize benefits. In this paper, several issues at the frontier of DFAM research are highlighted. First, the need is described to include as-manufactured mechanical and other physical properties, such as topology and shape optimization and generative design, during computational design. AM processes rarely produce parts with homogeneous composition and isotropic properties, so design methods and tools should not assume them. Second, the topic of designing for the AM process chain is important since AM-fabricated parts typically need postprocessing operations, such as support removal, finish machining, heat treatments, etc. DFAM methods need to incorporate the entire process chain, not just the AM process, which is explored with an example from metal powder bed fusion. Third, potentially, the largest benefit of AM can be realized by radically rethinking product architectures. Examples of an electric motorcycle and an assistive exosuit illustrate the ideas and potential benefits. Finally, some thoughts on design for 4D printing are offered, specifically for 3D printed morphing and deployable systems that utilize the shape memory effect.

Additive manufacturing systems integration

This research explores real-time database systems’ evolution, focusing on unique features and the addressed challenges. It examines the role of multi-material additive manufacturing quality domain databases in innovation and maintaining standards. It also looks at the challenges of implementing quality manufacturing systems from a technology, organization, and people of European Manufacturing research perspective. The study offers a new perspective on reconfigurable intelligent surfaces with multi-material additive manufacturing with system integration, discussing its applications and digital products’ transformative potential. Enhancing multi-material additive manufacturing capabilities redefines the industries, creating a strong communication culture by adopting quality integration of quality and robotics while exploring the future of mathematics complexity in optimizing manufacturing education. The paper also explains the statistical classification of historical technology in manufacturing engineering education by flagging the platform‘s role of opportunities in secure research collaboration. The manufacturing horizontal is essential for effectively managing the multi-material additive manufacturing system through advanced technology to quality management integration. Certified advanced training and competency development econophysics show the multi-material additive manufacturing systems development influence on the production theories and mechanics of complex electronics. To enable, for example, communication links and cellural multi-material additive manufacturing integrations research for new technologies.

The role of generative design and additive manufacturing capabilities in developing human–AI symbiosis: Evidence from multiple case studies

AbstractThe benefits of additive manufacturing (AM) extend beyond the attributes of physical products and production processes they enable. Experience with AM can augment the way design is approached and can increase opportunities to pivot toward less familiar design tasks. We begin this qualitative study with a natural experiment made possible by an exogenous shock: the COVID‐19 pandemic. Through a three‐stage case study approach using a grounded theory‐building method, we contrast AM usage among a set of firms, half of which pivoted their resources away from their traditional production and toward a response to this shock. We engage in an abductive reasoning approach to consider common threads in AM capabilities that facilitated this pivoting. Our analyses suggest that the advanced use of generative design (GD), a category of computational technologies enabling novel and optimized design, is a critical attribute of these firms that ended up pivoting to make COVID‐related products. Specifically, firms with experience applying this capability demonstrated a unique ability to pivot during this shock and emphasized their valuation of AM‐enabled agility. We revisited these firms 2 years after initial contact and found that GD was associated with higher levels of innovation and was largely viewed by designers as a mechanism driving double‐loop learning. Overall, our study provides insights into the symbiosis between human and artificially intelligent GD, and the role of such symbiosis in advancing AM capabilities.

Supply chain resilience and improving sustainability through additive manufacturing implementation: a systematic literature review and framework

Additive manufacturing (AM) is rapidly transforming supply chains across various sectors. This study explores the current academic literature on AM applications in the supply chain and practitioner literature to explore the application of AM across various sectors. It then identifies AM’s role in achieving supply chain resilience and environmental sustainability. Key themes addressed in the literature have also been discussed. TCM (Theory, Characteristics and Methodology) framework has been used to identify the research gaps and provide future research directions. The study also proposes a research framework and propositions based on AM characteristics and capabilities required to achieve supply chain resilience and environmental sustainability through AM. This study extends the AM literature to present an integrated approach towards simultaneously achieving resilience and environmental sustainability. The study reveals how the AM characteristics of design freedom, part consolidation and on-demand tool-less manufacturing aid in achieving the twin benefits. The research propositions could be taken by researchers interested in exploring the field further. The findings of this study will enable the decision-makers contemplating adopting AM, in making informed decisions and be better prepared.

A Novel Approach Toward the Integration of Fully 3-D Printed Surface-Mounted Microwave Ceramic Filters

A first approach toward the integration of heterogeneous electronic circuit technologies and fully 3-D printed ceramic microwave devices is discussed in this work. Additive manufacturing (AM) capabilities are explored for the development of multifunction surface-mount compact components used in different RF front-ends’ scenarios. Monolithic ceramic bandpass filters (BPFs) are designed to operate in the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$X$</tex-math> </inline-formula> -Band and to assess the typical limitations of ceramic stereolithography (SLA) processes. A post-fabrication tuning method based on a laser engraving strategy is presented to overcome the manufacturing constraints and carry out the filters’ correction. 2.5-D and 3-D printed four-pole filters were fabricated and tuned using the proposed methodology.

Powder‐Based Additive Manufacturing: A Critical Review of Materials, Methods, Opportunities, and Challenges

As a 0D material, powder particles can be used to create almost any complicated engineering component by utilizing the high‐performance manufacturing capabilities of additive manufacturing (AM). Although powder‐based AM methods provide an outstanding practical value and development for modern manufacturing world, they continue to face challenges such as a lack of accessible categories, temperature restrictions, and poor performance of molded components. Therefore, researching for new AM materials and procedures has become an extremely necessary endeavor. For this purpose, a firm grasp of the current state of the art of powder‐based AM technologies is imperative. Hence, herein, a comprehensive review is presented on the most widely used powder‐based AM methods, and the materials used by these methods. For each method, the development and current state, operating principles, limitations, and future prospects are summarized. In contrast, for materials, their classifications, properties, and preparation methods are explored in great detail, while also commenting on the specific compatibilities between powder materials and powder methods. Industrial and commercialized applications of powder‐based AM are also presented in this work. Finally, the limitations of the current powder‐based technologies are highlighted, with comments regarding the future of this field.

Break it down: comparing the effects of lecture- and module-style design for additive manufacturing educational interventions on student designers’ learning and creativity

ABSTRACT The growing presence of additive manufacturing (AM) in engineering has resulted in a consequent need for AM and design for AM (DfAM) educational interventions in design. Several researchers have proposed AM and DfAM educational interventions; however, some argue that these efforts might not be sufficient to develop higher-level skills (e.g., leveraging AM capabilities for creative design). Prior work suggests that longer, spaced educational interventions are more effective in encouraging learning and information retention; however, these interventions could also be time-consuming and expensive to implement. Our aim in this research is to compare two variations of a DfAM educational intervention: (1) a module-style intervention spread over two sessions with the introduction of DfAM evaluation metrics, and (2) a lecture-style intervention completed in a single session with no evaluation metrics introduced. From our results, we see that students from the module-style intervention reported a greater increase in their DfAM self-efficacy and reported having given a greater emphasis on part consolidation and feature size. However, the structure of the educational intervention did not influence the creativity of ideas generated by the students. These findings highlight the utility of module-style DfAM educational interventions toward increasing DfAM self-efficacy, but not necessarily design creativity.

AN OVERVIEW ON THE DESIGN VARIANTS FOR ORGANIZATION OF THE LIQUID FILM COOLING IN LPRE COMBUSTION CHAMBERS

Abstract. New technologies always create a trend to modernize and improve existing designs with new opportunities. At present, additive technologies have one of the most significant development rates among other manufacturing technologies. For modern liquid-propellant rocket engines, there is also a general trend towards increasing the efficiency of engines, finding new technological solutions that make it possible to simplify manufacturing technology, reduce technological costs and increase reliability. In this paper, known design solutions which employ film cooling for thermal protection of the walls of the engine chamber are considered. The main ways of organizing internal cooling are analyzed, the main mechanisms that define the thermal protection of the walls of the LRE chamber are considered. An overview of the existing design variants of devices which organize internal film cooling is given. The design solutions for film cooling of both the list of the real engines RD-105, RD-106, RD-0110, RD-115, RD-119 and known patent solutions are considered. The main features of such devices are shown and the influence of some design differences on the efficiency of the film cooling is analyzed. The main characteristics defining the efficiency of the device for film cooling are given. A review and analysis of the implemented design solutions for film cooling showed that the most efficient designs use the following elements, such as a gas-dynamic redan, a profiled wall of the predetermined space, and various types of inlet and outlet slots. Each design decision is based on the results of experimental testing of the engine. All these elements of film cooling design are very dependent on the accuracy of the manufacturing technology. Capabilities of additive manufacturing allow make it possible to create new designs with stable geometric characteristics in the form of a single part. The paper considers the options for applying the SLM additive manufacturing technology to create the design of the film cooling rings for liquid-propellant rocket engines.

Deconvolution volumetric additive manufacturing

Volumetric additive manufacturing techniques are a promising pathway to ultra-rapid light-based 3D fabrication. Their widespread adoption, however, demands significant improvement in print fidelity. Currently, volumetric additive manufacturing prints suffer from systematic undercuring of fine features, making it impossible to print objects containing a wide range of feature sizes, precluding effective adoption in many applications. Here, we uncover the reason for this limitation: light dose spread in the resin due to chemical diffusion and optical blurring, which becomes significant for features ⪅0.5 mm. We develop a model that quantitatively predicts the variation of print time with feature size and demonstrate a deconvolution method to correct for this error. This enables prints previously beyond the capabilities of volumetric additive manufacturing, such as a complex gyroid structure with variable thickness and a fine-toothed gear. These results position volumetric additive manufacturing as a mature 3D printing method, all but eliminating the gap to industry-standard print fidelity.