Distilling design methodologies for additive manufacturing from case studies

PurposeThis paper aims to provide a comprehensive overview of the recent applications of additive manufacturing (AM) research and activities within selected universities in the Republic of South Africa (SA).Design/methodology/approachThe paper is a general review of AM education, research and development effort within selected South African universities. The paper begins by looking at several support programmes and investments in AM technologies by the South African Department of Science and Technology (DST). The paper presents South Africa’s AM journey to date and recent global development in AM education. Next, the paper reviews the recent research activities on AM at four selected South African universities, South Africa AM roadmap and South African AM strategy. The future prospects of AM education and research are then evaluated through a SWOT analysis. Finally, the paper looks at the sustainability of AM from an education perspective.FindingsThe main lessons that have been learnt from South African AM research activities within selected universities are as follows: AM research activities at South African universities serve as a platform to promote AM education, and several support programmes and investments from South Africa’s DST have greatly enhanced the growth of AM across different sectors, such as medical, manufacturing, industrial design, tooling, jewellery and education. The government support has also assisted in the actualisation of the “Aeroswift” project, the world’s largest and fastest state-of-the-art AM machine that can 3D print metal parts. The AM research activities within South Africa’s universities have shown that it is not too late for developing countries to start and embrace AM technologies both in academia and industry. Based on a SWOT analysis, the future prospects of AM technology in SA are bright.Practical implicationsResearchers/readers from different backgrounds such as academic, industrial and governmental will be able to learn important lessons from SA’s AM journey and the success of SA’s AM researchers/practitioners. This paper will allow the major investors in AM technologies and business to see great opportunities to invest in AM education and research at all educational levels (i.e. high schools, colleges and universities) in South Africa.Originality/valueThe authors believe that the progress of AM education and research activities within SA’s universities show good practice and achievement over the years in both the applications of AM and the South African AM strategy introduced to promote AM research and the educational aspect of the technologies.

Applications of additive manufacturing in the construction industry – A forward-looking review

Additive Manufacturing (AM) processes have undergone a considerable evolution in terms of industrial applicability. From prototyping applications, AM has evolved to become a competitive technology to manufacture end products in comparison with conventional manufacturing. Despite that, the environmental impact advantage of AM is limited to some production scenarios and depends on several factors: high geometric complexity, weight reduction enabled by topology optimisation, light-weight product to be assembled for transportation. Considering production cost, AM process for metal-based components proved to be often more expensive than those produced by conventional approaches. To provide new piece of knowledge in the domain of AM applicability, in this paper a comparative analysis of costs and energy demand for additive, subtractive and mass conserving manufacturing processes is presented and applied to two different Ti-6Al-4V case studies (namely, an axisymmetric and a T-shape component). Turning/milling, hot forging and EBM were analysed and compared one another. The modelling and the results were analysed with varying the product complexity, the batch size, the method for accounting for the credit arising from recycling and the extent of light-weighting obtained by AM application. The result is a framework enabling informed process design and selection with varying production scenarios.

The primary goal of this study is to create a magnetic levitation system for additive manufacturing (AM) applications. The emphasis of this research is placed on Laser Directed Energy Deposition via Powder Feeding (LDED-PF). The primary benefit of using a magnetic levitation system for AM applications is that the levitated geometry is expected to be a portion of the final part manufactured, thus eliminating the need for a substrate and reducing the post-processing operation requirement. Two novel levitation systems were designed, optimized, and manufactured. The design, optimization, and analysis were first conducted in the simulation environment using ANSYS Maxwell and then tested with experiments. The newly developed systems depicted a much-improved performance compared to the first prototype developed in a previous article written by the authors. The newly developed systems had an increase in levitation height, the surface area for powder deposition activities, the time available for AM operations, and the ability to support additional mass within the limits of allowable inputs. The compatibility of the levitation system with AM applications was also verified by testing the impact of powder deposition and the ability of the levitated disc to support added mass as a function of time with minimal loss in performance. This article also highlights the development of a novel feedback PID controller for the levitation system. To improve the overall performance of the controller, a feedforward controller was added in conjunction with the PID controller. Finally, the levitation system was shown to highlight control over levitation height and maintain constant levitation height with the addition of an added mass using the feedback controller.

Additive manufacturing encompasses a set of low-cost and highly versatile tools used to prototype and fabricate three-dimensional (3D) objects with ease. In most of the additive manufacturing techniques, materials are deposited layer by layer until a 3D object is reproduced. Several additive manufacturing techniques have been developed in the previous decade, and the application of additive manufacturing has increased in various industrial sectors. However, there are still drawbacks associated with additive manufacturing techniques, necessitating further study and development. In this study, we review the techniques and materials used in additive manufacturing. The vast majority of additive manufacturing processes are still based on open-loop control or implement some local controllers for specific variables (such as temperature), making them susceptible for errors. This study presents a review of the different additive manufacturing techniques, examples of academic and commercial efforts to improve the control systems for additive manufacturing, as well as the application of additive manufacturing in different fields such as aerospace, electronics, arts, and biomedical. The article ends highlighting the advantages of utilizing a closed-loop control system in additive manufacturing and discussing the work needed for further development.

Bioceramics have frequent use in functional restoration of hard tissues to improve human well-being. Additive manufacturing (AM) also known as 3D printing is an innovative material processing technique extensively applied to produce bioceramic parts or scaffolds in a layered perspicacious manner. Moreover, the applications of additive manufacturing in bioceramics have the capability to reliably fabricate the commercialized scaffolds tailored for practical clinical applications, and the potential to survive in the new era of effective hard tissue fabrication. The similarity of the materials with human bone histomorphometry makes them conducive to use in hard tissue engineering scheme. The key objective of this manuscript is to explore the applications of bioceramics-based AM in bone tissue engineering. Furthermore, the article comprehensively and categorically summarizes some novel bioceramics based AM techniques for the restoration of bones. At prior stages of this article, different ceramics processing AM techniques have been categorized, subsequently, processing of frequently used materials for bone implants and complexities associated with these materials have been elaborated. At the end, some novel applications of bioceramics in orthopedic implants and some future directions are also highlighted to explore it further. This review article will help the new researchers to understand the basic mechanism and current challenges in neophyte techniques and the applications of bioceramics in the orthopedic prosthesis.

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.

The capabilities of Additive Manufacturing (AM) techniques has grown rapidly in recent years, however, current available metal powders for AM processes, such as Powder Bed Fusion and Directed Energy Deposition, are limited and primarily fabricated through atomization processes; the atomization process is capable of producing metal powders 15 µm to 150 µm in size, uniform size distribution, and spherical shape. Despite the advantages of atomization process, iron or nickel-based Oxide Dispersion Strengthened (ODS) powders, with nanocrystalline microstructure, cannot be produced with the atomization process because of the high temperature of yttrium (III) oxide (Y2O3, 2425 °C) compared to iron (Fe, 1538 °C), nickel (Ni, 1668 °C), chromium (Cr, 1907 °C) and aluminum (Al, 660 °C), thus, uniform dispersion of Y2O3 is problematic for ODS powders. In this work, a combination of Mechano-Chemical Bonding (MCB) process and Mechanical Alloying (MA) by planetary ball milling (BM) will be implemented to produce ODS powders suitable for AM applications. The MCB process fractures and uniformly disperse the Y2O3 nanoparticles and the nanoparticles are bonded on the surface of the master particles (Ni and Cr). Also, the MA process, because of the constant fracturing and cold-welding of the elemental particles, produces alloyed ODS powders with uniform size distribution, near spherical shape, and nanocrystalline microstructure. The objectives of this research work (1) adjust the processing parameters for the MCB+BM technique and investigate the effects of the process parameters on the size, morphology, and microstructure of the ODS powders and (2) use Ni-based ODS powder particles with optimal shape, size, size distribution, and microstructure on Laser Engineering Net Shaping (LENS) AM machine. Ni-based ODS powder particles nearly spherical in morphology, average particle size of 15 μm, uniform size distribution, uniform distribution of Y2O3, existence of the strength-hardening precipitate, and nanocrystalline microstructure were produced. The resultant Ni-based ODS powder particles were successfully used on a LENS AM machine to produce coupon specimen. The coupon specimen microstructure contains γ-NiAl matrix and γ’-Ni3Al strength hardening phase.

Additive manufacturing (AM) applications are taking up the challenges of engineering manufacturing, as AM technology sets give extensive advantages in terms of designing, analysis and part printing. Now, we find extensive applications in the medical field because one can print a medical implant as per individual patient’s match, which provides better comfort to the patient, and it uses material that suits the human body. Medical implants have complex shapes, need extensive customiation and have different tribological properties at different locations. Conventional manufacturing processes and materials are not able to take this challenge. AM technologies can easily print different types of materials as per the printing capability of 3D printing machines. The need is to study the medical implants’ tribological properties, with better part durability, when made through AM and improve patient comfort. The study is carried out with the help of the available literature on the different materials used in 3D printing. This study is a review-based work, where we try to identify the tribological behaviour of different materials as used for various medical applications. We have explored new and upcoming materials to help medical professionals for better applications. 3D printed medical implants provide accuracy as per the requirement of medical applications. Tribological properties like wear and friction are inherent with materials. This study discusses some tribological behaviour of different materials in the context of medical applications. Today, replacement arthroplasty is a common medical procedure, and joint replacement is clinically feasible. Thus, the biotribology of total hip arthroplasty and total knee arthroplasty is also discussed in the chapter. Implants are commercially available for medical applications, but they are not customized. Today, AM technologies are readily available to design and manufacture different materials as per individual requirements. They play an effective role in developing medical implants with different materials, processes and designs. Many materials have high-performance properties with excellent compressive tensile and bending strengths. These implant materials are used successfully to manufacture artificial knee joints, bone implants and other medical applications. It is found that 3D printed implants have lesser wear depth as compared to traditionally manufactured implants. Further, the area of prosthetics for rehabilitation needs extensive research and development.

PurposeThis paper aims to discuss additive manufacturing (AM) in the context of applications for musical instruments. It examines the main AM technologies used in musical instruments, goes through a history of musical applications of AM and raises the questions about the application of AM to create completely new wind instruments that would be impossible to produce with conventional manufacturing.Design/methodology/approachA literature research is presented which covers a historical application of AM to musical instruments and hypothesizes on some potential new applications.FindingsAM has found extensive application to create conventional musical instruments with unique aesthetics designs. It’s true potential to create entirely new sounds, however, remains largely untapped.Research limitations/implicationsMore research is needed to truly assess the potential of additive manufacturing to create entirely new sounds for musical instrument.Practical implicationsThe application of AM in music could herald an entirely new class of musical instruments with unique sounds.Originality/valueThis study highlights musical instruments as an unusual application of AM. It highlights the potential of AM to create entirely new sounds, which could create a whole new class of musical instruments.

Additive manufacturing (AM) offers significant opportunities for product innovation in many fields provided that designers are able to recognize the potential values of AM in a given product development process. However, this may be challenging for design teams without substantial experience with the technology. Design inspiration based on past successful applications of AM may facilitate application of AM even in relatively inexperienced teams. While designs for additive manufacturing (DFAM) methods have experimented with reuse of past knowledge, they may not be sufficient to fully realize AM's innovative potential. In many instances, relevant knowledge may be hard to find, lack context, or simply unavailable. This design information is also typically divorced from the underlying logic of a products' business case. In this paper, we present a knowledge based method for AM design ideation as well as the development of a suite of modular, highly formal ontologies to capture information about innovative uses of AM. This underlying information model, the innovative capabilities of additive manufacturing (ICAM) ontology, aims to facilitate innovative use of AM by connecting a repository of a business and technical knowledge relating to past AM products with a collection of knowledge bases detailing the capabilities of various AM processes and machines. Two case studies are used to explore how this linked knowledge can be queried in the context of a new design problem to identify highly relevant examples of existing products that leveraged AM capabilities to solve similar design problems.

Advances in Medical Applications of Additive Manufacturing

Additive Manufacturing (AM) applications have expanded significantly from rapid prototyping to high-end products such as complex spare parts. AM has enabled advantages of reduced material usage, geometric freedom, and production automation, shaping the future of the manufacturing industries. With the rapid expansion of AM applications, feedstock materials have developed noticeably, from polymers and ceramics to metals and composites. The progress in metal feedstock material discoveries has empowered the exploration of implementing new AM technologies. Fused Filament Fabrication (FFF) is one of the most common and cost-effective material extrusion AM technologies. This study explores the effect of the infill pattern on the tensile mechanical properties of metal parts produced via FFF, using two feedstock materials, 17-PH stainless steel and copper. Two approaches are designed to investigate the results: experimental tensile test, and Finite Element Analysis (FEA) with digital twin reconstruction method. Results show that 17-4 PH Stainless Steel samples with a triangular infill exhibited a 42% drop in ultimate tensile strength compared to solid infill. However, it also revealed a 34% reduction in mass, cost saving of 36%, and a faster fabrication with a 25% reduction in lead time. At the same time, copper samples with triangular infill exhibited a 22% drop in ultimate tensile strength and a 12% mass reduction. However, it revealed a similar lead time with only a 3% reduction. A Scanning Electron Microscope (SEM) was used to investigate the parts’ internal structure and average pore size, to understand the failure mode of the test specimens.

Additive manufacturing (AM) is a novel manufacturing technology that can create highly customized products with more complex geometries than traditional techniques. Despite its significant advantages, including the freedom of design, mass customization, and ability to produce complex structures, AM consumes a large amount of energy and incurs high costs. In addition, AM suffers from long production cycles and low production efficiency in the large-scale manufacturing of metal structures. This study offers a review of the existing literature focused on metal AM technology. To avoid the shortcomings of AM and highlight its benefits, which are widely used for manufacturing in combination with casting. The current combination application of AM and casting is reviewed to provide solutions to the problem of manufacturing large metal components from the perspective of the use of different AM technology and quality control in casting. However, such integration is insufficient for producing large castings with complex shapes, structures, or multiple features. Therefore, a novel method for integrating AM into casting to enable the manufacture of large scale metal parts with complex shapes is introduced as a topic for possible future research. This method divides complex castings with multiple features into an AM processing part and the casting substrate. The complex features were processed by AM on the fabricated casting substrate. This study provides a review of the application of AM into casting and presents a novel idea for the integration application of AM and other processes. This promising method has significant value for future study.

Addressing the challenges for the industrial application of additive manufacturing: Towards a hybrid solution