Additive Manufacturing and Qualification of an Active Piezoelectric Transducer in an Ocean‐depth Environment With Practical Application

Today, additive manufacturing technology has brought revolutionary changes to the materials and manufacturing industries. While polymer printing and metal 3D printing have been extensively researched, ceramic printing has emerged as a new trend in research. Ceramic additive manufacturing not only shares the characteristics of additive manufacturing but also faces greater challenges due to the higher melting temperatures and inherent brittleness of ceramics compared to polymers and metals. Ceramic materials possess some excellent performance characteristics. Additive manufacturing technology makes it possible to produce complex ceramic parts with shorter production cycles, lower costs, and retaining the characteristics of traditionally manufactured products. This article introduces the specific working modes of ceramic additive manufacturing technology, including SL, DLP, TPP, DIW, FDM, UP, SLS/SLM, LOM, and BJ3DP printing technologies. The current research status of ceramic additive manufacturing is discussed, as well as the preparation of slurries and the basic requirements for successful ceramic printing.

A comparison of additive manufactured to injection molded Martian regolith based polymer matrix composites

This paper focuses on an emerging manufacturing technology called Additive Manufacturing (AM) and its potential to become a more efficient and cleaner manufacturing alternative. This work is built around selected case companies, where the benefit of AM compared to other more traditional technologies is studied through the comparison of resource consumption. The resource consumption is defined as raw materials and energy input. The scope of this work is the application of AM in the scale model kit industry. The method used is the life cycle inventory study, which is a subtype of life cycle assessment (LCA). The result of the paper is the quantification of raw materials and energy consumption. The outcomes shows that AM has higher efficiency in terms of materials usage, as a higher proportion of materials ending up in the final product. Injection Molding (IM), on the other hand, wastes a significant proportion of raw materials in components that are not part of the final product. If the same or similar raw materials are used in both manufacturing methods, the advantage is clearly with AM. However, AM has higher energy consumption in comparison to the injection molding technique (IM). In terms of energy consumption, AM only has an advantage in this area when working with a very low production volume. The analysis of the energy consumption shows that most of the energy used in AM is to create the final product, while IM only uses a fraction of the total energy to produce the final product. AM technologies are still very new but have the potential for development and reduction of energy consumption in the future. Added to this potential is the higher materials usage efficiency of AM, which reduce the waste of materials and the energy, embedded in them. These two factors are likely to position AM as cleaner manufacturing alternative.

Owing to freedom of design, simplicity, and ability to handle complex structures, additive manufacturing (AM) or 3D printing of ceramics represents a promising enabling technology and has already been used to produce geometrically complex ceramic components and ceramic metamaterials. Consequently, novel applications for additively manufactured ceramics, which leverage their structural, high temperature, and chemical-resistant properties, have been proposed in areas ranging from electrical engineering and micro/nanoelectronics to chemical engineering to biology. Polymer derived ceramics (PDCs) represent a relatively new class of materials within additive manufacturing. PDCs enable the development of ceramic parts patterned via low-cost polymer 3D printing methods followed by pyrolysis in a high temperature process in which the polymer itself forms a ceramic often in the absence of any ceramic filler. PDCs have served as a feedstock for various 3D printing techniques for which a wide range of physiochemical factors can be tailored to optimize the ceramic manufacturing processes. In particular, the silicon and carbon-rich polymeric microstructure of PDCs offers a high degree of tunability and potential to achieve a closely defined combination of functional, thermomechanical, and chemical properties. In this review, we cover mechanisms underlying the design and manufacture of ceramics via 3D printing and pyrolysis of preceramic polymers, focusing on chemical formulations, printing technologies, and the mechanical performance of the ceramic network from microscale to scale. We also summarize experimental data from the literature and present qualitative and quantitative comparisons between different AM routes to provide a comprehensive review for 3D printing of PDCs and to highlight potential future research.

Machine learning assisted material development for lithography-based additive manufacturing of porous alumina ceramics

Additive manufacturing (AM), an enabler of Industry 4.0, recently opened limitless possibilities in various sectors covering personal, industrial, medical, aviation and even extra-terrestrial applications. Although significant research thrust is prevalent on this topic, a detailed review covering the impact, status, and prospects of artificial intelligence (AI) in the manufacturing sector has been ignored in the literature. Therefore, this review provides comprehensive information on smart mechanisms and systems emphasizing additive, subtractive and/or hybrid manufacturing processes in a collaborative, predictive, decisive, and intelligent environment. Relevant electronic databases were searched, and 248 articles were selected for qualitative synthesis. Our review suggests that significant improvements are required in connectivity, data sensing, and collection to enhance both subtractive and additive technologies, though the pervasive use of AI by machines and software helps to automate processes. An intelligent system is highly recommended in both conventional and non-conventional subtractive manufacturing (SM) methods to monitor and inspect the workpiece conditions for defect detection and to control the machining strategies in response to instantaneous output. Similarly, AM product quality can be improved through the online monitoring of melt pool and defect formation using suitable sensing devices followed by process control using machine learning (ML) algorithms. Challenges in implementing intelligent additive and subtractive manufacturing systems are also discussed in the article. The challenges comprise difficulty in self-optimizing CNC systems considering real-time material property and tool condition, defect detections by in-situ AM process monitoring, issues of overfitting and underfitting data in ML models and expensive and complicated set-ups in hybrid manufacturing processes.

This report summarizes work performed to assess the potential for utilizing additive manufacturing (AM) to substantially improve either the availability, performance or cost basis for tools and components that are required for geothermal energy production. A systematic cataloging of geothermal activities, associated technologies, and current manufacturing methods was first undertaken. This included literature reviews as well as interviews with subject matter experts, service companies and OEMs. An industry workshop was held as part of this portion of the project to obtain input and concerns from a broad range of OEMs, service providers and end users. This workshop was also used to gage the current level of AM activity in industry, receptiveness to the use of AM manufactured parts, and any up front concerns that may exist. A summary of the workshop is presented in this report. Representative components and assemblies and their current manufacturing methods were then analyzed by additive manufacturing experts at a company called Senvol to determine the feasibility and required steps for producing parts by additive manufacturing. A step by step description of conventional manufacturing of the parts was also performed to establish a manufacturing baseline for comparison purposes. This analysis also considered and described the benefits of additively manufacturing the parts in terms of specific AM systems, material availability for AM, dimensional requirements and potential economic advantages. Details of the manufacturability assessment were summarized in a report which is included as a chapter in this document. The analysis of the AM subject matter experts was then be used by techno-economic analysts to perform a comparative economic evaluation of the manufacturing of select technologies by AM and conventional approaches. This activity leveraged ORNL expertise and prior experience in other applications. A framework based on assessing cost, volume production considerations, and time to manufacture was created to more easily discern the advantages or disadvantages of additive versus conventional manufacturing methods. The report concludes with a general assessment of the current applicability of AM for geothermal technologies, AM gaps and needs related to typical geothermal hardware, and the potential benefits and impacts of AM to geothermal energy production.

Ceramic additive manufacturing (AM) has been demonstrated as a capable method to fabricate piezocomposite acoustic transducers that exhibit augmented sensitivity, increased bandwidth, and controlled directivity by virtue of geometry. These improvements are intrinsic to the novel piezoelectric ceramic structure, which may be printed in forms that cannot be fabricated through conventional manufacturing methods. The AM process allows for functionally-graded apertures, 3-3 piezocomposite structures, and auxetic lattices which have been simulated, printed, and measured with compelling results. This presentation expands upon previous work completed through a collaboration between Lithoz America, LLC (Lithoz), MSI Transducers Corp. (MSI), and the MITRE Corporation (MITRE) to produce novel piezoelectric structures and validate acoustic and hydrostatic pressure performance of 1-3 piezocomposite structures under operationally relevant conditions. The presentation will encompass a discussion of Finite Element Analysis (FEA) of piezoelectric metamaterials conducted at MITRE, the lithography-based ceramic manufacturing (LCM) process of said structures at Lithoz, and empirical measurements of piezoelectric and acoustical specifications of the printed structures conducted at MSI. Finally, test data recorded at Woods Hole Oceanographic Institute (WHOI) will be shown, demonstrating the resilience of AM 1-3 piezocomposite under 10 000 PSI of hydrostatic pressure derived by means of in-situ electrical impedance measurements.

The exceptional speed and quality achieved through injection molding have made it a great tool for high-volume production. However, the time-consuming process of debugging molds makes it expensive and leads to resource wastage. In response to the fast-growing demand for low-cost and fast production, additive manufacturing (AM) emerges as a promising candidate for cost-effective mold design and fabrication. This innovative approach not only circumvents the high initial investment of tooling associated with traditional injection molding but also offers significant advantages in terms of flexibility in design and manufacturing. Moreover, it provides the potential for creating customized molds on demand, allowing for reduced lead times and enabling rapid production. In this study, a comparative analysis is conducted to evaluate an injection mold insert produced using traditional machining processes and AM. An injection mold insert is designed for pharmaceutical applications and then manufactured using a computer numerical control (CNC) machine tool and two popular AM processes — fused deposition modeling and stereolithography. A combination of three critical AM process parameters (i.e., layer thickness, build angle, and infill rate or post-curing time) is selected and used for fabricating the injection mold inserts; meanwhile, sustainability and quality are evaluated. More specifically, the total energy consumption is quantified and compared for the three manufacturing processes, and the unit manufacturing cost is computed comprising energy cost, labor cost, and materials cost. In addition to sustainability measures, the mechanical strength in terms of hardness of the mold inserts is also investigated as their ability to withstand the high pressures encountered during the injection molding process affects the number of molding cycles before a failure. The dimensional accuracy is also experimentally analyzed to evaluate whether the injection molded products will be manufactured to appropriate tolerances. The results of this study confirmed the feasibility of adopting AM techniques as a viable alternative for injection mold insert manufacturing with lowered unit manufacturing costs and reduced energy consumption. The lower mechanical performance of additive-manufactured mold inserts compared with CNC-machined metal parts suggests a reduced number of molding cycles it can withstand, necessitating further research efforts. Addressing this challenge underscores the need for future studies to enhance the mechanical properties of additive-manufactured molds for expanded applicability of AM techniques in the field of rapid tooling used for mold production. The findings of this work present promising cost and energy-saving possibilities through the adoption of AM techniques, providing broader implications for sustainability and circular economy practices.

Purpose This paper studies the feasibility of additive manufacturing (AM) processes and their potential materials to produce mold inserts for injection molding (IM) of plastic parts. This study aims to describe the technological advancements and practical implications of integrating AM with IM to produce plastic parts, reducing the gap and determining the feasibility of AM for insert production. Design/methodology/approach A literature search of different databases was done. Applying the PRISMA methodology, the 67 most relevant articles between 2013 and 2024 were selected. From these, a bibliometric analysis was performed, and the main results regarding the mechanical properties and the number of injection cycles achieved by inserts were extracted. Findings Material jetting (MJT), vat photopolymerization via ultraviolet light laser (VPP-UVL) and laser powder bed fusion using metal powders (PBF-LB/M) are the most useful AM processes reported in the literature to produce inserts for IM. Studies show that the maximum number of successful injection cycles achieved with these AM inserts has been 116, 85 and more than 500 cycles, respectively. The molded geometry, the injected material and the IM parameters influence the number of injection cycles, being the injection pressure, the mold temperature and the injection temperature the most critical parameters to consider in extending the life of the inserts. Originality/value To the best of the authors’ knowledge, this study provides the first systematic review with a comprehensive overview of this innovative approach to evaluate the emerging directions, current barriers and future potential of using AM with IM to manufacture plastic parts. As such, this study highlights the primary findings in the literature concerning AM processes and the materials commonly used to manufacture inserts for IM.

Acrylonitrile Butadiene Styrene (ABS) is a common thermoplastic polymer that has been widely employed in the manufacturing industry due to its impact resistance, tensile strength, and rigidity. Additive manufacturing (AM) is a promising manufacturing technique being used to manufacture products with complex geometries, but it is a slow process producing mechanically inferior products when compared to traditional production processes like injection molding (IM). Thus, our hybrid manufacturing (HM) process combining materials extrusion AM and IM to create a single article was investigated in this study, in which eleven batches of specimens were made and extensively tested. These include the AM, IM, and hybrid manufactured (HYM) samples, in which the HYM samples were made by inserting AM substrates into the IM tool and were varied in infill density of AM preforms and geometries. The HYM samples outperformed AM parts in terms of mechanical performance while retaining customizability dependent on the HYM processing parameters, and the best mechanical performance for HYM samples was found to be comparable to that of IM samples, implying that the overmolding process in HM had primarily improved the mechanical performance of AM products. This work leads to a deeper knowledge of applications to confirm the optimal component fabrication in high design flexibility and mass production.

Additive manufacturing (AM) is finding increasing application in engineering, especially in manufacturing. As a result, new designs and machines not previously possible due to the restrictions of conventional manufacturing methods may be made. Nevertheless, the same AM parts require post-processing using conventional machining methods such as turning which is the subject of this study. This study provides a comparative analysis of the technological assurance of Ti-6Al-4V parts made via AM using selective laser melting (SLM) and conventional manufacturing methods. The effects of machining parameters such as cutting speed, depth of cut, and feed on the surface roughness of machined Ti-6Al-4V parts are studied. The study concluded that at low feed (0.12 mm/rev.) and low and average depth of cut (0.3 mm and 0.5 mm), the best surface roughness was obtained on the 3D printed samples rather than on the samples obtained using the conventional manufacturing method. In addition, an alternative surface roughness measurement scheme is proposed, which not only allows for measuring the surface roughness, including multiple aspects, but also for identifying possible surface defects in AM parts.

Mechanical Characterization of High-Temperature Carbon Fiber-Polyphenylene Sulfide Composites for Large Area Extrusion Deposition Additive Manufacturing

Advanced Energy systems require large, complex components produced from materials capable of withstanding severe operating environments (high temperature, pressure, corrosivity). Such parts can be difficult to source, as conventional material processing technologies must be tailored to ensure a safe and cost effective approach to large-scale manufacture of quality structural advanced alloy components that meet the performance specifications of AE systems. (HIP/PM) has shown advantages over other manufacturing methods when working with these materials. For example, using HIP’ing in lieu of casting means significant savings in raw material costs, which for expensive, high-nickel alloys can be considerable for large-scale production. Use of HIP/PM also eliminates the difficulties resulting from reactivity of these materials in the molten state and facilitates manufacture of the large size requirements of the AE industry, producing a part that is defect and porosity free, thus further reducing or eliminating time and expense of post processing machining and weld repair. New advances in Additive Manufacturing (AM) techniques make it possible to further expand the benefits of HIP/PM in producing AE system components to create an even more robust manufacturing approach. Traditional techniques of welding and forming sheet metal to produce the HIP canisters can be time consuming and costly, with limitations on the complexity of part which can be achieved. A key benefit of AM is the freedom of design that it offers, so use of AM could overcome such challenges, ultimately enabling redesign of complete energy systems. A critical step toward this goal is material characterization of the required advanced alloys, for use in AM. Using Haynes 282, a high nickel alloy of interest to the Fossil Energy community, particularly for Advanced-UltraSuperCritical (AUSC) operating environments, as well as the crosscutting interests of the aerospace, defense and medical markets, this research pursued three new methods of manufacturing these advanced alloys: 1) Directly built AM parts; 2) AM cans for HIP/PM; and 3) AM cans produced in the final part material. The project utilized Carpenter atomized A-282 in varied mesh sizes customized for both AM and HIP, ExOne’s binderjet technology, the fastest metal 3D printing technique on the market at the current time, coupled with an alloy specific sintering profile to produce a sufficiently dense part for final HIP by Bodycote. Final parts were subjected to chemical and physical property tests and results were compared to published and gathered data. Chemistry results for all the parts were within the published criteria. Furthermore, the AM and HIP/PM parts showed measurable improvement over previous A282 HIP/PM results, in part due to an improved HT spec, and a marked improvement over results from A282 castings. These results indicate that combining AM and HIP/PM in the manner set forth in this project provides a credible manufacturing approach of these activities are set forth in this Final Technical Report.

Comparative study on life cycle assessment of components produced by additive and conventional manufacturing process