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In recent decades additive manufacturing (AM) has evolved from a prototyping to a production technology. It is used to produce end-use-parts for medical, aerospace, automotive and other industrial applications from small series up to 100,000 of commercially successful products. Metal additive manufacturing processes are relatively slow, require complex preparation and post-processing treatment while using expensive machinery, resulting in high production costs per product. Design for Additive Manufacturing (DfAM) aims at optimizing the product design to deal with the complexity of the production processes, while also defining decisive benefits of the AM based product in the usage stages of its life cycle. Recent investigations have shown that the lack of knowledge on DfAM tools and techniques are seen as one of the barriers for the further implementation of AM. This paper presents a framework for DfAM methods and tools, subdivided into three distinct stages of product development: AM process selection, product redesign for functionality enhancement, and product optimization for the AM process chosen. It will illustrate the applicability of the design framework using examples from both research and industry. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) has been around for decades while it has been at the focus point of attention for home users and industry for only a few years. The reasons for this recent awareness can be attributed to the simplicity of the process, which allows it to be used to make almost any shape in any material. This is one of the reasons companies investigate the possibilities of AM as a strategic advantage in their line of business.. In this paper studies are presented in which the introduction of AM technologies within industry is the main focus. Design for AM methodologies are presented and linked to commercial successful introduction of AM in industry. It is shown that for this introduction the role of product (re)design for AM is of major importance to successfully apply AM as a production methodology. A new (re) design strategy for AM based product development is presented, from a product life cycle viewpoint (section 2) and a product level (section 4.1) [ABSTRACT FROM AUTHOR]

Thanks to the opportunities offered by additive manufacturing (AM) processes, design rules are evolving to lead to lighter and stiffer parts with really more complex shapes than those obtained by conventional processes. Worldwide, new tools of assistance to the design are developed, gathered under the naming “Design for Additive Manufacturing” (DfAM). However, most of the DfAM methods suggested in the literature remain focused on only one component and are not considering the product as a system of components. Moreover, optimizations are mainly limited on reducing the mass or the number of parts, and more rarely on adding some functions. In this article, a new approach is presented to realize a multifunctional optimization of a mechanical system (MS). A methodology is first proposed in order to improve a product by using the AM opportunity. Then, to quantify the improvements of an optimized system, a new design indicator appointed “functional improvement rate” is defined. Finally, a case study, applied to a compressed-air Wobbler engine, is presented to demonstrate the relevance of the methodology and the functional improvement rate. The design adapted to traditional manufacturing is compared to a part-by-part optimized design and a multifunctional optimized design, both adapted to additive manufacturing. [ABSTRACT FROM AUTHOR]

3D-printing has been used to create prototypes during the development phase for more than 20 years. Now, functional parts can be printed directly in specific metal powders using similar layer-by-layer techniques. The additive method is unlike traditional mass production manufacturing methods in many ways, creating new possibilities for designers to realise new and different design ideas previously impossible to manufacture. When products are mass produced, there is a desire to improve manufacturability. This is traditionally done by a designer with knowledge about certain manufacturing methods altering design choices to make it cheaper to manufacture. This paper shows different design for AM (DfAM) methods where performance and part cost are both of interest. It adds to existing research by classifying design for additive manufacturing in two different classes; process-driven and designer-driven shaping of parts. A cost-prediction model for Selective Laser Melting (SLM) printed parts is suggested as an initial step to choose parts for redesign from an economical perspective. A case study of a missile launcher beam redesigned for additive manufacturing using three different approaches is presented. Differences and similarities in design methods are discussed and the redesigned parts are compared for mass and cost. It is shown that redesigning for AM can reduce mass but depending on part size and print speed, the part can become more expensive than the original design, creating a need to know the customer value of what the redesigned part provides, in this case, the value of reduced mass. [ABSTRACT FROM AUTHOR]

[Display omitted] • Recent developments in multi-material additive manufacturing (MMAM) were comprehensively reviewed. • The applications of MMAM were discussed regarding various materials and AM methods. • The aspect of MMAM design, modeling, post-processing, and analysis was summarized. • Limitations, challenges, future trends of MMAM were highlighted. Extensive research on nature-inspired cellular metamaterials has globally inspired innovations using single material and limited multifunctionality. Additive manufacturing (AM) of intricate geometries using multi-materials provides additional functionality, environmental adaptation, and improved mechanical properties. Recently, several studies have been conducted on multi-material additive manufacturing (MMAM) technologies, including multi-materials, methodologies, design, and optimization. However, in the past six years, very few or no systematic and complete reviews have been conducted in this research domain. This review intends to comprehensively summarize MMAM systems and the working principles of its fundamental processes. Herein, the Multi-material combinations and their design, modeling, and analysis strategies have been reviewed systematically. In particular, the focus is on applications and opportunities for using MMAM for several industries and postprocessing MMAM fabricated parts. Furthermore, this review identified the limitations and challenges of existing software packages, MMAM processes, materials, and joining mechanisms, especially at the multi-material interfaces. Finally, we discuss the possible strategies to overcome the aforementioned technological challenges and state the future directions, which will provide insights to researchers and engineers designing and manufacturing complex nature-inspired objects. [ABSTRACT FROM AUTHOR]

Advances in additive manufacturing hardware have enabled the creation of lattice structures for engineering purposes; however the use of standard CAD software for the design of lattice structures is grossly inefficient, time consuming, and can lead to processing issues. To assist designer engineers that intend to implement large lattice structures a highly customisable free open source method of generating periodic lattice structures directly to the generic STL format has been developed. Programmatic method also offers a significant advantage to designers seeking to optimise or conduct finite element simulations on lattice structures allowing a batch export of both STL parts and a geometrically equivalent FE beam models. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM), particularly Selective Laser Melting (SLM) has enabled development of lattice structures with unique properties. Through control of various parameters lattice structures can produce unique mechanical, electrical, thermal and acoustic properties, and have received much research attention. Despite the increasing volume of published data on the mechanical response of specific SLM lattice structures, there exists no overarching analysis. This work addresses this identified deficiency by providing a comprehensive summary of the experimental data reported on the mechanical response of SLM lattice structures. The design, fabrication and performance of SLM lattice structures are reviewed and the quality of data reported is analysed to inform best-practice for future studies. This comprehensive data summary enables meta-analysis of the reported mechanical performance of SLM lattice structures, providing insight into the bounds of their technical capabilities. Correlations were identified between the relative density and mechanical properties of many unit cell topologies consistent with the predictions of the Gibson-Ashby model, indicating its usefulness in describing and predicting the behaviour of SLM lattice structures. This review provides designers with a compiled resource of experimental data and design for AM tools to inform future design applications of SLM lattice structures and facilitates their further commercial adoption. Unlabelled Image • A review of the design, fabrication and mechanical performance of Selective Laser Melting (SLM) lattice structures. • Reported data on the mechanical performance and properties of a broad range of SLM lattice structures is compiled. • Meta-analysis of reported data allows insights into the applicability of the Gibson-Ashby model to SLM lattice structures. [ABSTRACT FROM AUTHOR]